Aminotroponiminato(chloro)germylene Stabilized Copper(I) Iodide Complexes: Synthesis and Structure

Reaction of an aminotroponiminato­(chloro)­germylene [(i-Bu)2ATIGeCl] (1) (ATI = aminotroponiminate) with CuI in acetonitrile afforded an aminotroponiminato­(chloro)­germylene stabilized copper­(I) iodide complex [{(i-Bu)2ATIGeCl}2(Cu4I4)­(CH3CN)2] (2) with a tetrameric distorted cubane type Cu4I4 core. The reaction of compound 1 in dichloromethane with CuI in the presence of 2 equiv of pyridine resulted in the first germylene stabilized copper­(I) iodide complex [{(i-Bu)2ATIGeCl}­(CuI)­(C5H5N)2] (3) with a monomeric CuI core. A reaction of compound 1 with equimolar amounts of CuI and pyridine in dichloromethane resulted in a copper­(I) iodide complex [{(i-Bu)2ATIGeCl}2(Cu2I2)­(C5H5N)2] (4) with a dimeric Cu2I2 core. Interestingly, an interconversion between compounds 3 and 4 and conversion of compound 2 to compounds 3 and 4 under suitable conditions are also reported. The compounds 2–4 have been characterized by multinuclear NMR spectroscopy and single-crystal X-ray diffraction studies. The copper atoms in all these complexes are tetracoordinate, and the Ge­(II)–Cu­(I) bond lengths in complexes 2, 3, and 4 are 2.341(1), 2.308(1), and 2.345(1) Å, respectively.