J. Chem. Soc., Perkin Trans. 1, 1997 3117 ... Fachbereich Chemie der Philipps-Universität Marburg, Hans-Meerwein-Straße, 35032 Marburg, Germany ... Mixed diorganozincs (RZnCH2SiMe3; R = alkyl, aryl) undergo selective transfer of the R group in a 1,4-fashion to various Michael-acceptors. ... Diorganozincs are a useful class of organometallic intermedi- ates.1 They can be readily prepared via iodine–zinc exchange2 or boron–zinc exchange3 and ...