MOLECULAR AND CRYSTAL-STRUCTURES OF DIMERIC CALCIUM-BIS[BIS(TRIMETHYLSILYL)AMIDE] AND CALCIUM-BIS[BIS(TRIMETHYLSILYL)AMIDE].DME

X-ray crystal structures are reported for dimeric Calcium-bis[bis(trimethylsilyl)amide] 1 and Calcium-bis[bis(trimethylsilyl)amide] . DME 2. {Ca[N(SiMe3)2]2}2 1 crystallizes in the triclinic space group P1BAR with {a = 890.9(2); b = 1259.3(4); c = 2158.8(7)pm; alpha = 88.13(2); beta = 88.49(2); gamma = 72.25(2)-degrees; Z = 2}. The calcium atoms are three-coordinate with CaNt-bonds of 227 pm to the terminal ligand and CaN(b)-bonds of 247 pm to the bridging amido groups. Ca[N(SiMe3)2]2 . DME 2 crystallizes from n-hexane in the monoclinic space group C2/c with {a = 854.9(3); b = 1738.2(6); c = 2 042.1(6) pm; beta = 101.27(2)-degrees; Z = 4). The calcium atom has the coordination number four with CaN-bonds of 227 pm and CaO-distances of 240 pm. The molecule of compound 2 possesses C2-symmetry.