MOLECULAR-STRUCTURES OF A SILADIGERMIRANE AND A CYCLOTRIGERMANE

The crystal molecular structures of hexamesitylsiladigermirane (1, SiGe2Mes6, Mes = 2,4,6-trimethylphenyl) and hexamesitylcyclotrigermane (2, Ge3Mes6) have been determined by X-ray analysis. The crystals of 1.2CH2Cl2 (1) and 2.2CH2Cl2 (2) are isomorphous and isostructural and crystallize in monoclinic space group C2/c with Z = 4 of dimensions a = 20.659 (3) angstrom, b = 11.827 (2) angstrom, c = 23.288 (3) angstrom, beta = 105.30 (1)-degrees, and V = 5488.4 angstrom 3 for 1 and a = 20.657 (4) angstrom, b = 11.812 (2) angstrom, c = 23.289 (3), beta = 105.34 (1)-degrees, and V = 5479.8 angstrom 3 for 2. The three metal atoms of 2 form an equilateral triangle with a mean Ge-Ge bond length of 2.538 (2) angstrom. The silicon atom in the SiGe2 core of 1 is evenly disordered over the three sites with a resulting metal-metal mean bond distance of 2.508 (3) angstrom. The molecular structures of these compounds are discussed.