کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5274213 | 1385506 | 2008 | 5 صفحه PDF | دانلود رایگان |
The direct alkylation of silyl enol ethers with para-methoxybenzylic alcohols or their corresponding acetates was efficiently catalyzed by Bi(OTf)3 in CH3NO2 as the solvent. The reaction provided the α-benzylated carbonyl compounds in high yields after short reaction times using 1-2.5 mol % of the catalyst. Benzylic acetates other than para-methoxybenzylic acetates also underwent the reaction. High facial diastereoselectivities were observed with acetates derived from chiral α-branched para-methoxybenzylic alcohols. In addition, a catalytic reduction with Et3SiH as the reducing agent is reported.
Electron rich (RÂ =Â MeO, Me) benzylic alcohols or acetates serve as electrophilic reaction partners in the Bi(III)-catalyzed reaction with silyl enol ethers or hydrosilanes.
Journal: Tetrahedron Letters - Volume 49, Issue 8, 18 February 2008, Pages 1305-1309