STRUCTURES OF MONO- AND BIS(2-BUTENYL)ZIRCONIUM COMPLEXES IN SOLUTION AND THREO SELECTIVE INSERTION REACTION OF ALIPHATIC ALDEHYDES

Abstract
2-Butenyl group of Cp2ZrCl(C4H7), Cp2Zr(C4H7)2 and [Cp2Zr(C4H7)3·MgCl·THF] prepared from Cp2ZrCl2 and 2-butenylmagnesium chloride has essentially the (E)-configuration. These complexes react with aldehydes threo selectively at −78°C. Zr(OR)4/C4H7MgCl and Ti(OR)4/C4H7MgCl systems also serve as efficient reagents for threo selective synthesis of methylhomoallyl alcohols.