DOI： 10.1055/s-0031-1289895

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With the aid of an ionic liquid, palladium acetate was immobilized in the pores of silica gel, which was coated with polyethylene terephthalate. The heterogeneous catalyst was effective for Suzuki-Miyaura reactions of ortho-substituted aryl bromides, aryl triflates, and arylboronic acids in aqueous ethanol at room temperature, and could be re-used up to ten times.

DOI： 10.1055/s-0030-1260322

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The first total syntheses of the bicyclic sesquiterpenoids drechslerines A (1) and B (2), which were isolated from the algicolous fungus Drechslera dematioidea in the marine red alga Liagora viscida, has been accomplished starting from (S)-carvone (13) via three palladium-catalyzed reactions, namely, diastereoselective allylation, conjugate reduction, and carbon monoxide insertion, as the key reactions. (C) 2011 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2011.04.007

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The preparation of various (R)-Sulfur-MOP ligands with aryl and alkyl substituents on sulfur, and the application of these ligands to Pd-catalyzed asymmetric allylic alkylation of indoles is reported. The sulfur substituent served as an effective stereocontrol element, and in the case of the 2-i-PrPh substituent on sulfur, the allylation products from an array of simple and substituted indoles were obtained with high enantioselectivity (up to 95% ee).

DOI： 10.1021/ol102977b

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Palladium acetate was immobilized as Pd-SH-SILC (Pd-supported ionic liquid catalyst) in the pores of amorphous mercaptopropyl silica gel with the aid of an ionic liquid [bmim] BF(4). The heterogeneous Pd-SH-SILC was effective for catalytic hydrogenation of a variety of olefins at atmospheric pressure and room temperature. It withstood recycling up to 10 times by decantation.

DOI： 10.1039/c1gc15217c

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The total synthesis of the neo-clerodane diterpenoid salvinorin F was accomplished for the first time.

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The total synthesis of the recently isolated bicyclic sesquiterpenoid drechslerine B (2), isolated from the algicolous fungus Drechslera dematioidearare in the marine red alga Liagora viscida, has been achieved, starting from (8)-carvone (8), via an intramolecular aldol reaction and palladium-catalyzed carbon monoxide insertion as key reactions.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Palladium acetate was noncovalently immobilized as a supported ionic liquid catalyst (SILC) in a nanosilica dendrimer, PAMDMAM, with the aid of an ionic liquid to form a cluster catalyst of palladium nanoparticles. The pseudo-homogeneous heterogenized catalyst, Pd-nanoPAMDMAM-SILC, was effective for Suzuki-Miyaura reactions of ortho-substituted aryl bromides or aryl triflates without a ligand in 50% aqueous ethanol in air at room temperature. The catalyst could be re-used up to five times in 93% average yield after simple centrifugation. TON reached 176,000.

DOI： 10.1055/s-0029-1219816

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

MacMillan's imidazolidinone catalyst was immobilized as a supported ionic liquid catalyst (Mac-SILC) in the pores of silica gel with the aid of an ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide. The heterogenized organocatalyst was utilized for the enantioselective Diels-Alder reaction of cyclopentadiene and cinnamaldehyde, recovered by simple filtration and subsequent evacuation, and repeatedly used up to six times in 81% average chemical yield, 87% ee for endo- and 80% ee for exo-products. The Mac-SILC was effective for a variety of substrates.

DOI： 10.1002/adsc.200900865

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Thirteen- to eighteen-membered lactones were synthesized by ring-closing olefin-metathesis reactions of bis-olefins with heterogeneous Grubbs-supported ionic-liquid catalysts (SILCs), in which homogeneous Grubbs catalysts were confined in pores of alumina with the aid of an ionic liquid. The Grubbs-SILCs exhibited higher catalytic performance than their homogeneous counterparts and could be repeatedly recovered by simple filtration and re-used several times.

DOI： 10.1002/hlca.200900334

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DOI： 10.1055/s-0029-1218519

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A nano-silica dendrimer, poly(amidoamine)-grafted nanosilica (nano-PAMAM), catalyzed the Knoevenagel reaction of aryl and aliphatic aldehydes with various active methylene compounds at room temperature in good yields. The reaction conditions were mild enough that base-sensitive AcO or acid-sensitive THPO groups remained intact in the products. The catalyst was recycled up to 4 times in 78% average yield.

DOI： 10.1246/cl.2009.926

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The Henry reaction was catalyzed by 0.01 equiv of amino-propylated nanosilica particles (nano-NAP) in refluxing nitro alkanes to provide nitrostyrenes in good yields. The catalyst could be recycled up to three times in 76% average yield.

DOI： 10.1246/cl.2009.790

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Functionalization toward total synthesis of the hallucinogenic neoclerodane diterpenoid salvinorin A was accomplished via three double sequences: bis-enol triflate synthesis, palladium-catalyzed double carbonylation to the bis-enol triflate, and samarium diiodide-mediated double conjugate reduction. The configuration at C-12 was controlled by chelation-controlled diastereoselective reduction. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2009.04.053

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A highly general, active, and stable catalytic system was realized in the palladium-catalyzed Suzuki-Miyaura reactions of sterically hindered aryl bromides with arylboronic acids using biphenylene-substituted di-tert-butylruthenocenylphosphine (R-Phos) as a supporting ligand.

DOI： 10.1021/jo900550g

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Cuprous bromide was immobilized as a copper-supported ionic liquid catalyst (Cu-SILC) in the pores of amorphous mercaptopropyl silica gel with the aid of an ionic liquid, [bmim]PF(6). The heterogeneous Cu-SILC effectively and regioselectively catalyzed Huisgen [3+2] cycloadditions at room temperature in aqueous ethanol, and was used LIP to six times after simple decantation.

DOI： 10.1055/s-0028-1087926

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Grubbs olefin metathesis catalyst was immobilized as a ruthenium-supported ionic liquid catalyst (Ru-SILC) in pores of amorphous alumina with the aid of ionic liquid [hmim]PF(6). This Ru-SILC was effective for various olefin metathesis reactions such as intra- or intermolecular macrocyclization and dimerization, and used up to six times after simple decantation.

DOI： 10.1055/s-2008-1078570

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

The Mannich reaction of methylsilyl enol ether with arylaldimine proceeded in the presence of a catalytic amount of lithium chloride in dimethylformamide at room temperature. The reaction was mild enough to apply to aldimines having the AcO, TBDMSO, or MeS group. Microwave irradiation accelerated the reaction substantially to reduce reaction time. microwave heating.

DOI： 10.1055/s-2008-1078424

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

High activity in the palladium-catalyzed Suzuki-Miyaura reactions of aryl chlorides with arylboronic acids was furnished using biphenylene-substituted di-tert-butylruthenocenylphosphine (R-Phos) as a supporting ligand. Substrate combinations even for the construction of highly hindered tetra- ortho-substituted biaryls can be achieved in good to excellent yields with low catalyst loadings in short reaction times.

DOI： 10.1021/ol800567q

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Forskolin has been synthesized in 11 steps with a 17% overall yield from ptychantins A and B, which have been isolated from the liverwort Ptychanthus striatus in good yield. The I a-hydroxy group was furnished by stereoselective reduction of the corresponding carbonyl group by sodium cyanoborohydride. The 9 alpha-hydroxy group was introduced stereoselectively by epoxidation of Delta(9,11)-enol ether.

DOI： 10.1055/s-2008-1042930

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Total synthesis of salvinorin A (1), a neoclerodane diterpenoid having the most potent hallucinogenic activity and a selective K-opioid agonist, was completed in 20 steps starting from enantiomerically pure hydroxy-Wieland-Miescher ketone 5.

DOI： 10.1021/ol800101v

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Employing Pd(OAC)(2) immobilized on amorphous N,N-diethylaminopropyl alumina, Suzuki-Miyaura coupling of aryl halide with arylboronic acid was realized in 50% aqueous ethanol at room temperature, which enabled repeated use up to four times in 96% average yield and achieved a turnover number of 15 000.

DOI： 10.1055/s-2008-1032081

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

A new protocol for 1,4-conjugate addition of indoles to vinyl ketones has been developed, employing Lewis acidic ionic liquid immobilized on silica, ILIS-SO(2)Cl, as a catalyst, which exhibited an efficient, mild and recyclable nature. The reaction condition is applicable to various vinyl ketones and indoles. The mild nature of the reaction condition showed that the acetoxy or TBDMS group in indoles was maintained intact. The catalyst was used six times resulting in 86% average yield.

DOI： 10.1055/s-2008-1032082

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Natural enantiomers of unique tricyclic sesquiterpenoids, valeriananoids A-C 1-3, have been synthesized starting from bicyclo[2.2.2]octane-2,5-dione derivative 11, which was obtained by diastereoselective catalytic domino Michael reaction of oxophorone 5 with 8-phenylmenthyl acrylate 10 by LDA or silica-gel-base (NMAP-Li). The tricyclic ring was closed selectively by intramolecular 6-endo-trig mode cyclization of the ketyl radical, which was generated from keto-allylether 25 by either lithium or sodium naphthalenide. (C) 2007 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2007.04.095

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

A new organocatalytic procedure for the synthesis of bis(indolyl)methanes with acidic ionic liquid immobilized on silica gel (ILIS-SO2Cl) has been developed. The reaction condition is applicable to a variety of aryl and aliphatic aldehydes and indoles. The mild nature of the reaction conditions showed that the acetoxy or TBDMS group in the aldehyde was maintained intact. The catalyst was reused four times in 93% average yield.

DOI： 10.1055/s-2007-977453

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

A procedure for recyclable asymmetric cyclization leading to optically active Wieland-Miescher ketone analogue has been developed employing D-phenylalanine and D-CSA in [hmim]PF6 and dimethylimidazolidinone in 81% chemical yield and 74% enantiomeric excess in average after five uses. A Hajos-Wiechert ketone analogue was also synthesized in a similar manner.

DOI： 10.1055/s-2007-970740

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The stereoselective total synthesis of (+)-(Z)-laureatin is described. The 3,8-dioxabicyclo[5.1.1]nonane skeleton possessing trans-orientated alkyl substituents at the alpha,alpha'-positions to the ether linkage was stereoselectively constructed via formation of the oxetane arising from 4-exo cyclization of hydroxy epoxide existing on the oxocene core. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2006.12.082

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The stereoselective total synthesis of (-)-12,13-epi-obtusenyne is described. The oxonene skeleton possessing cis-orientated alkyl substituents at the alpha,alpha'-positions to ether linkage was stereoselectively constructed via cyclization of the corresponding hydroxy epoxide promoted by Eu(fod)(3).

DOI： 10.1246/cl.2007.278

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The stercoselective total synthesis of (+)-obtusenyne is described. The oxonene skeleton possessing trans-orientated alkyl substituents at the alpha,alpha'-positions was stereoselectively constructed via cyclization of the corresponding hydroxy epoxide promoted by Eu(fod)(3). (c) 2006 Published by Elsevier Ltd.

DOI： 10.1016/j.tetlet.2006.11.080

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Highly efficient Suzuki-Miyaura coupling of aryl halides with arylboronic acid was realized in 50% aqueous ethanol at room temperature employing Pd(OAc)(2) immobilized in diethylaminopropylated (NDEAP) alumina pores with the aid of [bmim]PF6, which enabled recycle use up to five times in 95% average yield and turnover number of two million.

DOI： 10.1039/b704098a

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The reaction of samarium diiodide with some cyclic and acyclic ketones tethering acyloxyalkyl side chains produced 2-hydroxy cyclic hemiacetals in moderate to good yields, in which an intramolecular addition of samarium ketyl radicals to distant ester carbonyls would be involved. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2006.08.126

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Michael addition of a 1,3-dicarbonyl compound to an alpha,beta-unsaturated carbonyl compound was effectively catalyzed by heterogeneous N,N-diethylaminopropylated silica gel (NDEAP) in water under microwave heating. The reaction condition was mild, practical, and environmentally benign. The sustainable nature of the catalyst was exemplified by re-use up to 5 times.

DOI： 10.1246/cl.2006.926

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Aldol reaction of trimethylsilyl enolate with aldehyde proceeded in the presence of a catalytic amount of a Lewis base, N-methylimidazole, and lithium chloride in DMF at room temperature. Not only aryl aldehyde but also alkyl aldehyde provided the aldol product in satisfactory yields. The reaction was mild enough to apply to the aldehyde having HO, AcO, THPO, TBDMSO, MeS, pyridyl or olefinic group. Microwave irradiation accelerated the reaction. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2006.05.074

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Forskolin ( 1), a highly oxygenated labdane diterpenoid and an activator of adenylate cyclase, has been synthesized in 12 steps and 12% overall yield from ptychantin A (4), which has been isolated from liverwort Ptychanthus striatus in good yield. The 1 alpha-hydroxy group was furnished by stereoselective reduction of the corresponding carbonyl group by sodium in t-BuOH. The 9 alpha-hydroxy group was introduced stereoselectively by epoxidation of Delta(9.11)-enolether. 1,9-Dideoxyforskolin (2), an inhibitor of glucose transporter, has been synthesized in 8 steps and 37% overall yield. The hydroxy group at C-1 was removed by solid-state thicarbonylimidazolation and subsequent radical cleavage.

DOI： 10.1021/jo060477e

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

gamma-Hydroxy-alpha,beta -unsaturated nitrile was obtained by the reaction of alpha-arylsulfinylacetonitrile with aldehyde in water, which was catalyzed by N,N-diethylaminopropylated silica gel. The overall transformation proceeded via five sequential reactions, 1,2-addition of acetonitrile, dehydration (Knoevenagel condensation), isomerization of the double bond, rearrangement of sulfinyl group (Mislow-Evans rearrangement) and hydrolysis of sulfinyl ester. The reaction condition was mild such that the AcO, TBMDSO or OTHP group remained intact in the products.

DOI： 10.1055/s-2006-941590

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A variety of tetrahydrobenzo[b]pyrans have been synthesized by sequential addition of arylaldehydes, cyanoacetate and then dimedone in water under microwave irradiation. A heterogeneous amine, N,N-diethylamino-propylated silica, was an effective catalyst for the reaction. The reaction with malononitrile provided the same result. The reaction condition was general to apply to the aldehyde having a Cl, NO2, OH, OMe, or CO2H group in satisfactory yield.

DOI： 10.3987/COM-06-10698

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DOI： 10.1021/ol060525h

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DOI： 10.1039/b603056b

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

An environmentally benign and sustainable Knoevenagel reaction of aldehyde with ethyl cyanoacetate has been achieved at ambient temperature in water employing 3-aminopropylated silica gel (NAP) as a catalyst. Wide applicability of the reaction is illustrated by the results that not only arylaldehydes of both electronic characters but also aliphatic aldehydes afforded the products. The reaction condition was so mild that aldehydes having acid- or base-sensitive substituents provided substituted alpha-cyano-alpha, beta-unsaturated esters. The catalyst has been efficiently recycled more than five times without any pre-treatment. Catalyst loading was successfully reduced to 0.0029 mmol% (TON = up to 9,226). This protocol was also applicable to the Knoevenagel reaction of malononitrile in good yields in water.

DOI： 10.1007/s11030-005-8107-0

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[GRAPHIC]
Pd-catalyzed monophosphinylation of (R)-2-bromo-T-iodo1,1'-binaphthyl with Ph2P(O)H afforded (R)-2-bromo-2'diphenylphosphinyl-1,1'-binaphthyl in good yield with excellent chemo selectivity and no observable racemization. Subsequent lithiation in the presence of excess thiosulfonate furnished an enantiomerically pure sulfenylation product, which was reduced to afford a chiral S-MOP ligand.

DOI： 10.1021/jo051581j

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Aldol reaction of trimethylsilyl enolate with aldehydes proceeded in the presence of a catalytic amount of a Lewis base, pyridine N-oxide, and lithium chloride in DMF at room temperature. Not only aryl aldehydes but also alkyl aldehydes provided the aldol products in satisfactory yields. The reaction was mild enough to apply to aldehydes having HO, AcO, THPO, TBDMSO, MeS, pyridyl, or olefinic groups.

DOI： 10.1055/s-2005-872664

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Domino Michael reactions of oxophorone and its derivatives 4 with Michael partners 3 have been effected to give bicyclo[2.2.2]octane-2,5-dione derivatives 7 by a catalytic amount of a Bronsted base (NMAP-Li) generated from N-methylaminopropylated silica gel (NMAP) and n-BuLi. The NMAP pellets were efficiently reused up to six times in 86% average yield. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2005.03.092

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The neo-trans-clerodane natural product, (-)-methyl barbascoate 1, has been synthesized for the first time starting from the known ketone 6 derived from (R)-(-)-Wieland-Miescher ketone analogue 5.

DOI： 10.1021/jo0478499

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Self-aldol condensation of an unmodified aldehyde has been effected by 3-N-methylaminoprophylated silica as a catalyst in supercritical carbon dioxide, to give an alpha,beta-unsaturated aldehyde (enal). Aldehydes having acid or base-sensitive substituents provided desired enals. (C) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2004.11.120

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Palladium acetate immobilized on reversed phase amorphous silica gel with the aid of an ionic liquid, [bmim]PF6, was highly efficient in the promotion of the Mizoroki - Heck reaction in pure water without a ligand up to the sixth re-use, in 95% average yield with TON and TOF 1,600,000 and 71,000 (h(-1)), respectively.

DOI： 10.1039/b502528a

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Transesterification of beta-ketoesters with various alcohols has been effected by N,N-diethylaminopropylated silica gel (NDEAP) as a catalyst in refluxing xylene. Generality of the reaction was demonstrated by successful transesterification of olefinic alcohols, tertiary alcohols and alcohols having acid- or base-sensitive substituents. The catalyst has been efficiently recycled more than five times without any re-activation.

DOI： 10.1055/s-2004-831309

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Palladium acetate was supported on amorphous silica with the aid of an ionic liquid, [bmim]PF6. The immobilized catalyst was highly efficient in promoting the Mizoroki-Heck reaction without a ligand in n-dodecane for at least six reuses, in 89-98% yields. The TON and TOF reached 68 400 and 8000, respectively.

DOI： 10.1021/ol049343i

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In the presence of a catalytic amount of optically active pyrrolidine derivatives derived from L-proline, conjugate addition of an unmodified aldehyde to 3-buten-2-one in [bmim]PF(6) was achieved to afford (2S)-5-keto-aldehyde in up to 59% ee. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.molcata.2003.11.035

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In the presence of a catalytic amount of lithium amide, the reaction of oxophorone with electron-deficient olefins afforded bicyclo[2.2.2]octane-2,5-dione derivatives in high yields. The reaction proceeds autocatalytically by an enolate of bicyclo[2.2.2]octane-2,5-dione, generated by an initial domino Michael reaction.

DOI： 10.1021/ol049948e

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A resolution-free route to chiral 2.2'-bis(pyridin-2-yl)-1.1'-binaphthyl ligands 2 was developed for the first time based on the photochemical CpCo(CO)(2)-mediated cycloaddition reaction of enantiopure 2.2'-dicyano-1.1'-binaphthyl 3 with 1.6-heptadiyne. 1,7-octadiyne, 1,8-nonadiyne, and 2.8-decadiyne. (C) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2004.02.155

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Dilithiation of optically active 2.2'-dibromo-1.1'-binaphthyl 2 with t-BuLi followed by carboxylation of the resulting dilithio-intermediate 3 with CO2 gave optically active 1.1'-binaphthyl-2.2'-dicarboxylic acid 1, which was further transformed to its dicyano derivative 4. Both of these transformations were carried out in a one-pot operation and the products were obtained in excellent yields with no observable racemization. (C) 2004 Elsevier Ltd. All right reserved.

DOI： 10.1016/j.tetlet.2004.02.156

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The seco- and rearranged-labdanes, chapecoderins A 1, B 2, and C 3 have been synthesized for the first time starting from (S)-(+)-Wieland-Miescher ketone analogue 11. Their absolute configurations have been determined as depicted in the structures 1, 2 and 3. (C) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2004.01.004

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MARCEL DEKKER INC  

The title compound has been synthesized from optically active lactone derived from (S)-(+)-Wieland-Miescher ketone analogue employing solid-state Baeyer-Villiger reaction.

DOI： 10.1081/SCC-120027252

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Self-aldol condensation of an unmodified aldehyde has been effected by N-methyl-3-aminopropylated silica as a catalyst in ionic liquid, [bmim]PF(6), to give an alpha,beta-unsaturated aldehyde (enal). Aldehydes having acid or base sensitive substituents provided desired enals in satisfactory yields. The reaction system has been efficiently recycled more than eight times.

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The stereoselective total synthesis of (+)-laurallene is described. The required key oxocene skeleton possessing trans-orientated alkyl substituents at the alpha,alpha'-positions was stereo selectively constructed via the cyclization of the corresponding hydroxy epoxide promoted by Eu(fod)(3). (C) 2003 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(03)00432-5

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1,9-Dideoxyforskolin 2 has been synthesized starting from ptyebantin A 3. (C) 2003 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(03)00236-3

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An efficient and versatile method for the stereospecific construction of alpha,omega-cis- and alpha,omega-trans-disubstituted eight- and nine-membered cyclic ethers was developed. Cyclization of the hydroxy epoxides promoted by Eu(fod)(3) proceeded via an S(N)2 process and exo mode to provide the corresponding cyclic ethers in excellent yields. (C) 2003 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(03)00335-6

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

A tricyclic sesquiterpenoid, valeriananoid A 1, has been synthesized via domino Michael reaction of oxophorone 4 and subsequent 6-endo-trig cyclization of a ketyl radical as key steps. (C) 2003 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(03)00064-9

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley Blackwell  

DOI： 10.15227/orgsyn.080.0195

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

(R)-(C10H6)(2)M-2 (M=SnMeCl2, SnMe2Cl, SnMe(OTf)(2), SnMe2OTf, SiMe2I) were synthesized as novel chiral 2,2'-bismetallic-1,1'-binaphthyl catalysts. The catalytic activities were evaluated in the Diels-Alder reaction of methacrolein and cyclopentadiene and the asymmetric acylation reaction of racemic 1-phenyl-1,2-ethanediol. (C) 2002 Published by Elsevier Science Ltd.

DOI： 10.1016/S0957-4166(02)00578-5

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Treatment of bicyclo[2.2.1]heptene having an exo- or endo-olefinic side chain with a catalytic amount of Grubbs' Ru carbene complex under ethylene atmosphere provided bicyclo[3.3.0]octene or bicyclo[4.3.0]nonene compounds by domino ROM-RCM reaction. (C) 2002 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4020(02)00690-7

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

The phytotoxins solanapyrones D (1) and E (2) have been synthesized from the decalone prepared by the domino Michael reaction of the kinetic enolate of optically pure acetylcyclohexene with methyl crotonate. The decalone was transformed into a solanapyrone core by equilibration into thermodynamically stable trans-decalone (11), dehydroxylation, and dehydration. Condensation of a methyl acetoacetate equivalent followed by cyclization installed a pyrone moiety. Introduction of a formyl or hydroxymethyl unit into the pyrone ring via Pummerer related reactions furnished solanapyrones D (1) and E (2).

DOI： 10.1021/jo0163602

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Chemical Society of Japan  

Dilithiation followed by bis-stannylation with Me3SnCl of (R)-2,2′-dibromo-1,1′-binaphthyl (2) and the subsequent redistribution reaction of resulting (R)-2,2′-bis(trimethylstannyl)-1,1′-binaphthyl (6) with SnCl4 gave the novel chiral Lewis acid catalyst (R)-2,2′-bis(dichloromethylstannyl)-1,1′-binaphthyl (4). The catalytic properties of 4 and its triflate 5 were investigated as the first chiral bis-metallic binaphthyl catalyst.

DOI： 10.1246/cl.2002.600

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Unmodified aldehydes add to vinylketones in 1,4-manner in ionic liquid, [bmim]PF(6), in the presence of a catalytic amount of propylamine grafted on silica. The ionic liquid involving the catalyst has been recycled intact without loss of efficiency.

DOI： 10.1039/b201900k

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Language：English   Publishing type：Research paper (scientific journal)  

It is important to select odorous molecules for experiments on olfaction and for the development of an electronic nose. Odorous molecules having a small number of conformers, namely structurally rigid molecules, are assumed to interact with a small number of types of olfactory receptor proteins or to interact with the proteins in a simpler manner than that of fairly flexible molecules. Focusing on the rigidity of molecular structures, we collected 287 odorous molecules from data sources, which included 1205 chemicals in total and a database of the 287 odorous molecules (DB⊙MOL) was created using CS ChemFinder Pro (version 5.0). The logarithmic value of the octanol/water partition coefficient (log P) and melting point, boiling point and vapour pressure of the molecules were estimated using CS Chem3D Pro. The database DB⊙MOL accumulates these estimated data in addition to literature values for odour quality, odour detection thresholds and the safety of molecules. The rigidity of the 287 molecules was further analysed by conformational analysis performed by molecular mechanics using Conformer® in CS Chem3D Pro (version 5) and 72 rigid odorous molecules were selected. The 287 molecules were also analysed based on atomic composition, substructure and molecular size. Sixty-two odorous molecules among the 72 rigid odorous molecules were further selected based on their atomic composition. The 62 rigid molecules with simple atomic composition that were finally selected should be useful for researchers in choosing odorous molecules for the study of olfaction, including the fields of molecular biology, physiology, structure-odour relationships and other fields of the study concerning odour.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Total syntheses of alpha-bisabol-1-one, curcumene, curcuphenol and elvirol have been accomplished via 1,4-conjugate addition of intact aldehydes to vinyl ketones followed by an intramolecular aldol condensation.

DOI： 10.1039/b200629b

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

The tetracyclic sesquiterpenoid (+)-cyclomyltaylan-5alpha-ol 1 has been synthesized starting from (S)-(+)-Hajos-Wiechert ketone analogue 10 via stereoselective Claisen rearrangement followed by SmI2-promoted reductive cyclisation. Thus, the absolute configuration has been established to be 2R, 3R, 4R, 5S, 6R, 7R (cyclomyltaylane numbering) as depicted in structure 1.

DOI： 10.1039/b111594b

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

A seco-labdane, chapecoderin A 1, has been synthesized starting from (S)-(+)-Wieland-Miescher ketone analogue 9. The absolute configuration has been determined to be 55,10S. (C) 2001 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(01)01647-1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Pd/C-catalyzed Heck reactions of aryl halides with olefins proceeded in moderate to satisfactory yields in ionic liquid [bmim]PF(6). The ionic liquid involving a catalyst was easily recycled. (C) 2001 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(01)00748-1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The title compounds have been prepared by treatment of 4-methoxy-3-phenylsulfinylmethyl-2H-pyrone derivatives with trifluoroacetic anhydride, followed by basic work-up. (C) 2001 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4020(01)00347-7

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Naked aldehydes directly add in a 1,4-manner to vinylketones in the presence of 0.2 equiv. of diethylamine in sealed tubes to provide 5-keto aldehydes. (C) 2001 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(01)00247-7

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The first total synthesis of (+)-rogioloxepane A is described. The alpha,omega -trans-disubstituted oxepene skeleton was stereoselectively constructed via cyclization of the hydroxy epoxide promoted by the (Bu3Sn)(2)O/Zn(OTf)(2) system. The proposed configurations of 6R and 13R were confirmed through this synthetic study. (C) 2001 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(00)02281-4

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The stereoselective formal synthesis of (+)-isolaurepinnacin is described. The required key oxepene skeleton possessing cis-oriented alkyl substituents at the alpha,omega -positions was stereoselectively constructed via the cyclization of the corresponding hydroxy epoxide promoted by the (Bu3Sn)(2)O/Zn(OTf)(2) system. (C) 2000 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(00)01880-3

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

[GRAPHICS]
A phytotoxin, solanapyrone E, has been synthesized from the decalone prepared by the domino Michael reaction of the kinetic enolate of optically pure acetylcyclohexene with methyl crotonate, After several transformations on the decalone ring, condensation of a methyl acetoacetate equivalent installed a pyrone moiety and introduction of a hydroxymethyl unit into the pyrone ring furnished solanapyrone E.

DOI： 10.1021/ol006893h

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

The reaction of enolates of 1,3-dicarbonyl compounds with alpha -halo-alpha, beta -unsaturated carbonyl compounds affords 2,4-diacyldihydrofuran derivatives in the presence of DBU in THF. Chemical manganese dioxide oxidation of the hydrofurans leads to 2,4-diacylfuran derivatives. Application of the protocol enables short-step syntheses of antitumor naphthofuran natural products.

DOI： 10.1039/b107180g

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Aldehydes directly add in a 1,4-manner to electron-deficient olefins in the presence of diethylamino(trimethyl)silane.

DOI： 10.1039/b005728m

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

The selection of odor-active conformers and the construction of a model for a targeted odor type, i.e., for the lily-of-the-valley odor, were examined. The disagreement of the odors of 1,3,4,5-tetrahydro-2-benzoxepin derivative 1 and 3-[4-(tert-butyl)phenyl]-2-methylpropanal (2) is discussed in terms of their stable conformers. The conformer active for the lily-of-the-valley odor was investigated by conformational analyses of several related compounds. Based on the integrated model consisting of the assumed active conformers (Fig. 5), compounds anticipated to possess the lily-of-the-valley odor were designed and synthesized. The odor of synthetic 7-(tert-butyl)-1,2,4,5-tetrahydro-3H-benzocyclohepten-3-one (8) and 3-[4-(tert-butyl)phenyl]cyclopentanone (13) were evaluated by perfumer, to have a floral odor and to recall the lily-of-the-valley anti lilac odors, respectively. Our methodology to design new odoriferous compounds. based on conformational analysis, selection of odor-active conformers, and construction of a model, proved to be satisfactory.

DOI： 10.1002/1522-2675(20010711)84:7<2051::AID-HLCA2051>3.0.CO;2-H

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

The syntheses of 7-sila-7H-dibenzo[c,g]fluorenes 1 were effected via dilithiation of 2,2'-dibromo-1,1'-binaphthyl (2) followed by cyclization of the resulting dianion with dihalosilanes: Me2SiCl2, Ph2SiCl2, and Ph2SiF2. The X-ray structural analysis of 7-sila-7, 7-diphenyl-7N-dibenzo[c,g]fluorene (1b) provided the first geometrical parameters of the 7-sila-7H-dibenzo[c,g]fluorene derivative in which the silole skeleton was found to be twisted in the C-2 symmetrical conformation due to the significant steric repulsion of the binaphthyl group fixed within the van der Waals radii. The photophysical study and semiempirical PM3 calculation suggested the presence of significant sigma*-pi* conjugation in the LUMO of the 7-sila-7N-dibenzo[c,g]fluorene 1 like a silole.

DOI： 10.1021/om000436n

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

DOI： 10.1021/jo000785r

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

An efficient and versatile method for the stereospecific construction of alpha,omega-cis- and alpha,omega-trans-disubstituted oxepane skeletons is described. Cyclization of the hydroxy epoxides promoted by a (Bu3Sn)(2)O/Zn(OTf)(2) system proceeded via an S(N)2 process and exo mode selectivity regardless of the configuration of the hydroxyl and the epoxy groups to provide the corresponding oxepanes in excellent yields. (C) 2000 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(00)01344-7

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Cyclization of hydroxy epoxides mediated by a (Bu3Sn)(2)O/Lewis acid system proceeded via an S(N)2 process and exo mode to provide the corresponding seven-membered cyclic ethers in high yield. (C) 2000 Elsevier science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(00)01345-9

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Brominative Si-Si cleavage of 3,4-disila-3,3,4,4-tetramethyl-3,4-dihydrodibenzo[c,g]phenanthrene (3a), LiAlH4 reduction of the resulting dibromide, and fluorination of the dihydride 14a thus gave 2,2'-bis(fluorodimethylsilyl)-1,1'-binaphthyl (7a) in high yield as the first isolated and fully characterized 2,2'-bis(halosilyl)-1,1'-binaphthyl. Similar conversion of the more sterically hindered 3,4-disila-3,3-dimethyl-4,4-diphenyl-3,4-dihydrodibenzo[c,g]phenanthrene (3b) also gave the corresponding bishydrosilane 14b. However, subsequent fluorination did not give the desired bisfluorosilane 7b but rather the hydrolyzed siloxane 6b. The syntheses of the disilanylene-bridged precursors 3 were effected via bis-silylation reactions of 2,2'-dibromo-1,1'-binaphthyl (DBBN, 2) with dihalodisilanes ClMe2SiSiMe2Cl, ClMe2SiSiPh2Cl, FMe2SiSiPh2F, and FPh2SiSiPh2F. Although ClMe2SiSiMe2Cl predominately gave the disilanylene-bridged product 3a, XMe2SiSiPh2X (X = F, Cl) produced not only the disilanylene-bridged product 3b but also the dimethylsilylene-bridged product 8a. FMe2-SiSiPh2F served better in preparation of the desired 3b than ClMe2SiSiPh2Cl. The sterically hindered FPh2SiSiPh2F did not give silylation products. The X-ray structural analyses of 3a and 3b provided the first geometrical parameters of the 2,2'-disilanylene-bridged-1,1'-binaphthyl derivatives. In comparison with the acyclic analogues and less sterically hindered disilanylene-bridged biaryls such as 2,2'-bis(trimethylsilyl)-1,1'-binaphthyl ((+/-)-1a), (R)(-)-2,2'-bis(dimethylphenylsilyl)-1, 1'-binaphthyl ((R)-(-)-1b), dibenzo-1,1,2,2-tetramethyl-1,2-disilacyclohexa-3,5-diene (12), and dithienodisilacyclohexadiene 13 the disilanylenebridged binaphthyls 3 were found to be highly strained due to the steric repulsion of the binaphthyl groups fixed in a narrow angle.

DOI： 10.1021/om0001523

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

A concise and simple synthesis of the valuable perfumery ingredient (R)-(-)-muscone 1 has been achieved through ring closing olefin metathesis (RCM) aided macrocyclization protocol as the key step. Commercially available starting material (R)-(+)-citronellal 3 has been employed as a building unit in preparing the acyclic diolefinic substrate 16, which in turn was exposed to bis(tricyclohexylphosphine)benzylideneruthenium dichloride catalyst 2 to afford the cyclic RCM reaction product 17 in 78% yield. Catalytic hydrogenation of 17 furnished enantiomerically pure (R)-(-)-muscone 1. (C) 2000 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4020(00)00333-1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Reaction of kinetic enolate of alpha'-substituted cyclohexenone derivatives with vinylselenoxides provided tricyclo[3.2.1.0(2.7)]-octane-6-one derivatives via domino Michael-Michael-substitution protocol. (C) 2000 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4020(00)00032-6

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Dinorsesquiterpenoid 1 is synthesised starting from (S)-(+)-Wieland-Miescher ketone analogue 5 via solid-state Baeyer-Villiger reaction as a key step.

DOI： 10.1039/b003571h

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Domino Michael-seleno Pummerer type reaction (additive seleno Pummerer type rearrangement) has been realised by the reaction of 1,3-dicarbonyl compounds with vinyl selenoxides in the presence of amine and chlorosilane.

DOI： 10.1039/b004912n

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Self-aldol condensation of naked aldehydes in the presence of diethylaminotrimethyl-silane with or without solvent provided unsaturated aldehydes. (C) 1999 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(99)01326-X

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Ruthenium-catalyzed ring-closing metathesis (RCM) reactions of various alpha,omega-bis(allyldimethylsilyl)-, bis(dimethylvinylsilyl)-, and bis(dimethylvinyloxysilyl)-substituted compounds are examined. The steric and electronic influences of the substrates on the RCM reaction were discussed. Although the successful ring-closing reactions are limited to seven- and eight-membered rings, disilacycloalkene derivatives constructed with -SiMe2-CH2-SiMe2-, -SiMe2-(CH2)(2)-SiMe2-, -SiMe2-O-SiMe2-, -SiMe2-N(Ph)-SiMe2-, and a vinylene unit in the ring system were obtained in good to reasonable yields under the mild reaction conditions. The limitation of the reactions is mainly ascribed to Si-C and Si-Si bonds being longer than the C-C bond in the ring system.

DOI： 10.1246/bcsj.72.821

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The novel tetracyclic sesquiterpenoid (+)-cyclomyltaylan-5 alpha-ol 1 has been synthesized starting from (S)-(+)-Hajos-Wiechert ketone analogue 3 via SmI2-promoted reductive cyclization as a key step. Thus, the absolute configuration has been established to be 2R,3R, 4R,5S,6R,7R (cyclomyltaylane numbering) as depicted in structure 1. (C) 1999 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(99)00338-X

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Norsesquiterpenoid 1 has been synthesised starting from (S)-(+)-Wieland-Miescher ketone analogue 3 via solid state Baeyer-Villiger oxidation as a key step.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Formylcyclopropanecarboxylates have been synthesized by diethylaminotrimethylsilane mediated tandem conjugate addition-alkylation of aldehydes to methyl alpha-haloaclylate generated in situ from methyl 2,3-dihalopropanoate. (C) 1999 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(98)02668-9

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MARCEL DEKKER INC  

Kinetically generated enolate of cyclohexenone when reacted with methyl 2,3-dichloropropanoate provided methyl tricyclo[3.2.1.0(2,7)]octane-1-carboxylate and its congeners via domino Michael-Michael-alkylation reaction.

DOI： 10.1080/00397919908086195

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Chemical Society of Japan  

First synthesis of optically active 2,2'-bis-silyl-substituted 1,1'-binaphthyl derivatives, (R)-(+)-2,2'-bis(trimethylsilyl)-1,1'-binaphthyl ((R)-(+)-1) and (R)-(-)-2,2'-bis(dimethylphenylsilyl)-1,1'-binaphthyl ((R)-(-)-2), has been accomplished by the direct bis-silylation of chiral 2,2'-dibromo-1,1'-binaphthyl (DBBN). The molecular structure and the absolute configuration of (R)-(-)-2 have been determined by means of X-ray crystallography.

DOI： 10.1246/cl.1999.1245

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The reaction of methyltrichlorosilane with an equimolar amount of allyl chloride in the presence of zinc powder proceeds quite smoothly in dimethylimidazolidinone (DMI) to give allyl(dichloro)methylsilane in high selectivity. Other RSiCl3 (R = isopropyl, tert-butyl, n-hexyl, phenyl, n-octyl, n-decyl) gave the corresponding allylated compounds, (CH2=CHCH2)-RSiCl2, highly selectively in high yield under the same conditions. Dimethyldichlorosilane and trimethylchlorosilane are also monoallylated. The reaction of 2 equiv of allyl chloride-Zn-DMI with methyltrichlorosilane gave the diallylated compound selectively. The reaction of methyltrichlorosilane with CE)-1-chloro-2-butene selectively afforded 1-methyl-2-propenyl-(methyl)dichlorosilane with allylic rearrangement. The reaction was also applied successfully to the allylation of polychlorodisilanes. ? 1998 American Chemical Society.

DOI： 10.1021/om9805133

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Chemical Society of Japan  

(Trimethylsilylmethyl)trimethyldisilene was generated photochemically from 1-phenyl-7-trimethylsilylmethyl-7,8,8-trimethyl-7,8-disilabicyclo[2.2.2]octa-2, 5-diene (masked disilene). UV spectrum and regioselectivity of the addition reaction of phenols to the disilene were discussed. The molecular structure of the masked disilene was also determined by single-crystal X-ray diffraction.

DOI： 10.1246/cl.1998.427

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