Ligand-Protected Strain-Free Diarylgermylenes

Abstract

Reaction of 2 molar equiv of 2,6-di(1‘-naphthyl)phenyllithium with bis[bis(trimethylsilyl)amino]germylene afforded the red, crystalline, stable bis[2,6-bis(1-naphthyl)phenyl]germylene [(bisap) 2 Ge, 6 ] in good yield. The structure of the solvate 6 ·C 6 H 6 was determined by single-crystal X-ray methods. The molecule features a largely strain-free conformation with a C−Ge−C angle of 102.72(9)° and Ge−C distances of 2.036(2) and 2.030(2) Å. These parameters are very close to those calculated for the di phenyl germylene prototype by ab initio methods [101.6°; 2.006 Å]. The two new wing-like 2,6-di(1-naphthyl)phenyl substituents appear to protect the germylene center of 6 in a very efficient way without inducing destabilizing distortions. Bis[2,4,6-triphenylphenyl]germylene [(triph) 2 Ge, 1 ] was also prepared. Germylenes 1 and 6 were oxidized to yellow products of the composition (triph) 2 GeO ( 2 ) and (bisap) 2 GeO ( 7 ), respectively. The compounds have been characterized by their mass spectra, which show the parent ions in full accordance with the proposed formulas.