Carbonyl Olefination by Means of a gem-Dichloride-Cp(2)Ti[P(OEt)(3)](2) System.
The preparation of highly substituted olefins by carbonyl olefination using a gem-dichloride-Cp(2)Ti[P(OEt)(3)](2) system was studied. The treatment of organotitanium species, formed by reaction with titanocene(II) species from gem-dichlorides having two alkyl substituents, with an aldehyde or ketone afforded tri- or tetrasubstituted olefins in good yields. Acyclic or cyclic trisubstituted vinyl ethers were also obtained by a similar reaction using carboxylic esters or lactones as carbonyl components.
Takeda
Takeshi
T
Department of Applied Chemistry, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan.
Sasaki
Rika
R
Fujiwara
Tooru
T