Nucleophilic additions to ketenes by (trimethylsilyl) lithium and by enolates

L Gong, R Leung-Toung, TT Tidwell

Index: Gong, Leyi; Leung-Toung, Regis; Tidwell, Thomas T. Journal of Organic Chemistry, 1990 , vol. 55, # 11 p. 3634 - 3639

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Citation Number: 25

Abstract

Reaction of t-Bu, C= C= O (5) with Me, SiLi at-78" C followed by trapping of the intermediate enolate with AczO gave t-BuzC= C (OAc) SiMe3 (9). Other ketenes gave similar products. Reaction of ketenes PhCR= C= O (R= Me, 13; R= Et, 3) with enolates CH2= C (OLi) R1 (R'= H, Me, t-Bu, Ph) at-78" C followed by warming to 25" C and hydrolysis gave vinyl esters PhCHRCO2C (R1)= CH2, along with 10% PhCHMeCOCH, COPh for R= Me, R'= Ph. ...