ORGANOSILICON CHEMISTRY I: CYCLOPROPANATION BY CARBENE OR CARBENOID ADDITION TO AN ALLYLIC SILANE

Abstract

The syntheses of tetra(dichlorocyclopropane)silane 2 and tetra(cyclo- propane)silane 3 have been accomplished using dichlorocarbene (:CCl₂) and carbenoid addition, respectively. Various phase transfer catalysts (PTC) have been tested for :CCl₂ addition to tetraallylsilane 1. 2-Benzilidine-N,N,N,N',N',N',-hexaethyl propane-1,3-diammonium dibromide (Dq-Br) was found to be effective in giving 2 in a yield above 80%. A modified synthetic route to 3 by the reaction of 1 with Zn-Ag couple and methylene iodide is also described. The success of the reaction has been attributed to an alternative work-up procedure.

KEY WORDS: Cyclopropanation; Phase transfer catalyst; Dichlorocarbene; Zn-Cu couple; Simmons-Smith reaction


Bull. Chem. Soc. Ethiop. 2006, 20(1), 55-60.