78905-13-2Relevant academic research and scientific papers
Stereoselective preparation of (E)- and (Z)-di- and trisubstituted 1,3-butadienes
Takeda, Takeshi,Tateishi, Keiichiro,Tsubouchi, Akira
, p. 4016 - 4021 (2015)
Abstract The reaction of γ-(trimethylsilyl)allyltitanocenes, generated by the desulfurizative titanation of trimethylsilyl-substituted allylic sulfides with the titanocene(II)-1-butene complex, with ketones produced β-hydroxy silanes with good to complete
Studies on the reactive species in fluoride-mediated carbon-carbon bond-forming reactions: Carbanion formation by desilylation with fluoride and enolates
Biddle, Margaret M.,Reich, Hans J.
, p. 4031 - 4039 (2007/10/03)
The reactive species in fluoride-mediated carbon-carbon bond-forming reactions was investigated. The regio- and diastereoselectivities of silanes reacting with cyclohexenone in the presence of a catalytic amount of fluoride was compared to the reactivity of analogous solvent-separated lithium ion pairs. Closely analogous behavior was observed, showing that carbanions and not siliconate complexes are the reactive species in the fluoride-catalyzed reactions. Spectroscopic investigations unambiguously show that phenylthiobenzyl anion will form by reaction of silane with tris(dimethylamino)sulfonium difluorotrimethylsilicate (TASF) or crypt[2.1.1]-solvated lithium enolates. The catalytic cycle runs smoothly with the crypt[2.1.1] complex of α-(phenylthio)benzyllithium as the initiator and enolate as the carrier of the desilylation reaction.
Synthesis of Vinylcyclopropanes from Epoxides
Schaumann, Ernst,Kirschning, Andreas,Narjes, Frank
, p. 717 - 723 (2007/10/02)
Ring-opening of epoxides 1 by heteroatom-substituted allyl anions 2 occurs with high regioselectivity.In situ tosylation of the resulting alkoxides 3 or tosylation of the corresponding alcohols 4 yields 4-pentenyl tosylates 5.Anion generation by deprotona
Hydroalumination and related reactions of phenyl 1-(trimethylsilyl)propadienyl sulfide followed by quenching with carbonyl compounds
Tanaka,Kanemasa,Tsuge
, p. 51 - 56 (2007/10/02)
Phenyl 1-(trimethylsilyl)propadienyl sulfide undergoes a hydroalumination with diisobutylaluminum hydride (DIBAH) or lithium butyl(diisobutyl)aluminum hydride (BL-DIBAH). The adduct anion derived from DIBAH is regioselectively trapped with carbonyl compounds at the position α to the phenylthio moiety to give 1,3-dienes as Peterson olefination products; the anion derived from BL-DIBAH is trapped at the position γ to the phenylthio moiety to give 3-buten-1-ols. Silylmetalation and stanylalumination on the same acceptor have been also briefly investigated as equivalent reactions.
Acid-Catalyzed Regioselective Acylation of α-Silylallylic Sulfides and Its Application to a Novel Cyclopentannelation and Furan Annelation
Hiroi, Kunio,Sato, Hiroyasu,Chen, Lih-Ming,Kotsuji, Kumiko
, p. 1413 - 1426 (2007/10/02)
Introduction of a silyl group at the α-position of allylic sulfides, followed by the aluminum chloride-catalyzed reaction of the resulting α-silylallylic sulfides with acid chlorides resulted in regioselective acylation at the γ-position of the allylic system to give γ-acylated vinylic sulfides, chemically equivalent to 1,4-dicarbonyl compounds.Heating of the products in refluxing benzene with an equimolar amount of p-toluenesulfonic acid produced 2-cyclopentanone derivatives.Treatment of the acylated products with an equimolar amount of concentrated sulfuric acid gave α-phenylthiofuran derivatives.These procedures provide a novel method for cyclopentannelation and furan annelation.Keywords - α-silylallylic sulfide; acid chloride; aluminum chloride; acid-catalyzed acylation; vinylic sulfide; 2-cyclopentanone; α-phenylthiofuran; furan; cyclopentannelation; furan annelation
Selective Condensation of titanium Reagent with Carbonyl Compounds
Furuta, Kyoji,Ikeda, Yoshihiko,Meguriya, Noriyuki,Ikeda, Nobuo,Yamamoto, Hisashi
, p. 2781 - 2790 (2007/10/02)
titanium reagent generated easily from allyl ethyl sulfides condensed with aldehydes to give erythro-β-hydroxy sulfides in highly regio- and stereoselective manner.In contrast, crotyl ethyl sulfide reacted with aldehydes affording δ-hydroxy vinyl sulfide exclusively.The substitution pattern of the starting sulfide can have a pronounced effect on the selectivity in this condensation reaction, erythro-β-Hydroxy sulfide obtained was transfromed stereoselectively to the trans-vinyloxirane or 1,3-alkadiene.
NEW TRANSFORMATIONS OF SUBSTITUED ALLENE SULPHOXIDES
Cutting, Ian,Parsons, Philip J.
, p. 4463 - 4464 (2007/10/02)
The preparation and reactions of trimethylsilyl substituted allene sulphoxides are described.Allenes (2) rearrange on warming to give α,β-unsaturated thiol esters.
Regioselective Acylation of Allyl Sulphides via α-Silyl Intermediates
Hiroi, Kunio,Chen, Lih-Ming
, p. 377 - 378 (2007/10/02)
Acylation of the α-trimethylsilylallyl sulphides (2) by reaction with the acid halides (3) (1.2 equiv.) in the presence of aluminium chloride (1.2 equiv.) in methylene dichloride at -78 deg C gave compounds (4a - i) in good yields with extremely high regi
