Strategies in the cyclopentadienyl chemistry of p-block elements

Abstract

Synthetic strategies in the cyclopentadienyl (Cp) chemistry of the groups 13-15 elements, are based on the following phenomena: (1) low barriers for haptotropic and dyotropic shifts, for sigmatropic rearrangements, and for other types of Cp migration; (2) stabilization of elements in their low-oxidation state by π-complexation; (3) tuning of steric and electronic effects by suitable ring substituents; and (4) easy homolytic and heterolytic cleavage of El-C(Cp) bonds. These strategies are applied to: (a) the formation of a Si2Me4 doubly bridged dicyclopentadienyl cobalt complex, (b) the chemistry of half-sandwich [Me5C5Ga] and sandwich [(Me5C5)2Si] complexes, (c) the formation of P6, (d) the deposition of Al, Ga, Si, Ge, and As from respective Cp-El precursor molecules, and (d) the "dynamic covalent chemistry" in ferrocenylgallium(III) compounds.