Michael reaction. IV. NaNH2 catalyzed one stage reaction between phenylacetic acid dialkylamides and cinnamic acid methyl ester or dialkylamides. Influence of reaction conditions on the stereochemistry
Michael reaction. IV. NaNH2 catalyzed one stage reaction between phenylacetic acid dialkylamides and cinnamic acid methyl ester or dialkylamides. Influence of reaction conditions on the stereochemistry
Titanium enolates and “ate” complexes of N,N-disubstituted amides and thioamides in the Michael reaction.
作者:Lilia Z. Viteva、Tzveta S. Gospodova、Yuri N. Stefanovsky
DOI:10.1016/s0040-4020(01)85243-1
日期:1994.1
The synthetic potential, regio- and stereoselectivity of titanium dialkylamide and dialkylthioamide enolates and “ate” complexes in reaction with some conjugate carbonyl compounds are investigated. Titaniumenolates react preferentially in 1,2-position while “ate” complexes afford 1,4-regiocontrol. The stereochemical behaviour of the latter follows in general the lithium and potassium precursors. Marked
Michael addition of phenylacetic acid dialkylamide and ester enolates to Z-methyl cinnamate. Dependence of the stereochemistry on the acceptor geometry.
作者:Lilia Viteva、Yuri Stefanovsky
DOI:10.1016/s0040-4039(00)97923-1
日期:——
The dependence of the stereochemical course on the acceptor geometry and on the metal counterion is demonstrated in the kinetic Michael addition of phenylaceticacid dialkylamide and ester enolates to Z-methylcinnamate. The results obtained are consistent with cyclic trasition state models.