Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, USA.
J Am Chem Soc. 2012 Mar 7;134(9):4045-8. doi: 10.1021/ja211874u. Epub 2012 Feb 22.
Reaction of the diarylgermylene Ge(Ar(Me(6)))(2) [Ar(Me(6)) = C(6)H(3)-2,6-(C(6)H(2)-2,4,6-(CH(3))(3))(2)] with tert-butyl isocyanide gave the Lewis adduct species (Ar(Me(6)))(2)GeCNBu(t), in which the isocyanide ligand displays a decreased C-N stretching frequency consistent with an n → π* back-bonding interaction. Density functional theory confirmed that the HOMO is a Ge-C bonding combination between the lone pair of electrons on the germanium atom and the C-N π* orbital of the isocyanide ligand. The complex undergoes facile C-H bond activation to produce a new diarylgermanium hydride/cyanide species and isobutene via heterolytic cleavage of the N-Bu(t) bond.
二芳基锗烷 Ge(Ar(Me(6)))(2) [Ar(Me(6)) = C(6)H(3)-2,6-(C(6)H(2)-2,4,6-(CH(3))(3))(2)] 与叔丁基异氰化物反应生成路易斯加合物 (Ar(Me(6)))(2)GeCNBu(t)，其中异氰化物配体的 C-N 伸缩振动频率降低，表明存在 n → π* 反馈键合相互作用。密度泛函理论证实，HOMO 是锗原子上的孤对电子和异氰化物配体的 C-N π* 轨道之间的 Ge-C 成键组合。该配合物易于发生 C-H 键活化，通过 N-Bu(t)键的异裂生成新的二芳基锗氢化物/氰化物物种和异丁烯。
