- Catalytic asymmetric synthesis of β-hydroxy ketones by palladium-catalyzed asymmetric 1,4-disilylation of α,β-unsaturated ketones
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1,4-Disilylation of β,β-unsaturated ketones with 1,1-dichloro-1-phenyl-2,2,2-trimethyldisilane proceeded in the presence of phosphine-palladium catalysts in benzene. High enantio-selectivity (up to 92%) was observed in the disilylation with dichloro[(R)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl] palladium(II) as a catalyst (0.5 mol %). The disilylation products, 1-(trimethyisilyloxy)-3-(dichlorophenylsilyl)propenes, were readily converted into optically active α-unsubstituted or anti α-substituted β-(phenyldimethylsilyl) ketones, the oxidation of which gave the corresponding optically active β-hydroxy ketones in high yields.
- Matsumoto, Yonetatsu,Hayashi, Tamio,Ito, Yoshihiko
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p. 335 - 346
(2007/10/02)
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- PALLADIUM-CATALYZED 1,4-DISILYLATION OF α,β UNSATURATED KETONES WITH 1,1-DICHLORO-1-PHENYL-2,2,2-TRIMETHYLDISILANE
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1,4-Disilylation of α,β-unsaturated ketones proceeded with 1,1-dichloro-1-phenyl-2,2,2-trimethyldisilane in the presence of a phosphine-palladium catalyst in benzene.Treatment of the disilylation products with an excess of methyllithium generated β-silyl lithium enolates, of which hydrolysis and alkylation gave β-(phenyldimethylsilyl) ketones and anti β-silyl α-alkyl ketones, respectively.
- Hayashi, Tamio,Matsumoto, Yonetatsu,Ito, Yoshihiko
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p. 4147 - 4150
(2007/10/02)
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