Reactions of a phosphavinyl Grignard reagent with main group mono-halide compounds

The reactions of a phosphavinyl Grignard reagent, [CyP=C(Bu')MgCl(OEt2)] Cy = cyclohexyl, with a variety of main group 13, 14 and 16 mono-halide compounds have been investigated. When the Grignard reagent is reacted with bromocatecholborane the terminal phosphavinyl complex, [(C6H4O2)B{C(Bu')=PCy}], is formed. Related terminal phosphavinyl tin and gallium complexes, [R3Sn{C(Bu')=PCy}], R = Me or Bu" and [IGa{C(Bu')=PCy}(2)], have been prepared by similar routes. The reaction of the Grignard reagent with PhSeCl has afforded a new lambda(5),lambda(5)-diphosphete, [{(Bu')CP(Cy)(SePh)}(2)], the mechanism of formation of which is discussed. The preparation of a phosphavinyl selenium compound, [(C8H4O2N)P=C(Bu')(SePh)], is also described. All compounds have been spectroscopically characterised and several have been crystallographically authenticated. (C) 2002 Elsevier Science B.V. All rights reserved.