Enantiomerically enriched 1-(N,N-diisopropylcarbamoyloxy)-1,3-dimethylallyllithium: stereochemistry of the stannylation, titanation, and the homoaldol reaction
作者:Oliver Zschage、Jan-Robert Schwark、Thomas Krämer、Dieter Hoppe
DOI:10.1016/s0040-4020(01)86586-8
日期:1992.9
Contrarely to our former assumption1,3, the title compounds 3 and 9 [(2E)- and (2Z)-isomer, (-)-sparteine or TMEDA complex] are substituted by means of trialkyltin halides in an anti-S(E)' process. The optically active allylstannanes, thus produced, and aldehydes undergo a stereospecific homoaldol reaction under the influence of TiCl4 which involves a second anti-S(E)' transmetallation.