Conformational Studies of Neopentyl- and Trimethylsilylmethyl-substituted Germyl Radicals by Electron Spin Resonance

Article abstract of DOI:10.1246/bcsj.57.796

Conformational analyses of a series of neopentyl- and trimethylsilylmethyl-substituted germyl radicals by electron spin resonance(ESR) were investigated on the basis of the modified cos²θ rule.Dimethylneopentylgermyl radical has the conformations with the neopentyl group rotating freely.On the other hand, dimethyl(trimethylsilylmethyl)germyl radical has the preffered conformations with trimethylsilylmethyl group eclipsing with the singly occupied orbital on a germanium atom.The ESR spectra of dineopentylmethylgermyl and bis(trimethylsilylmethyl)methylgermyl radicals showed the existence of two kinds of methylene protons due to th e nonplanar geometries and the slow inversion of these germyl radicals.Conformations of trineopentylgermyl and tris(trimethylsilylmethyl)germyl radicals are also discussed.