Bridging cyclopentadienyl MSn(IV) bonded polymetallic complexes: X-ray crystal structures of [(Me2SnCl)(CO)3MoC5H4C(O)CH2]2·CH2Cl2 and [(Ph3Sn)(CO)3WC5H4C(O)CH2]2·3H2O
摘要:
The dianions [(CO)(3)MC5H4C(O)CH2](2)(2-) reacted with RnSnX4-n in a 1:2 or 1:1 ratio to give tetranuclear complexes [(RnSnX3-n)(CO)(3)MC5H4C(O)CH2](2) (M = Mo or W; R = Ph or Me; X = Cl or Pr; n = 2 or 3), which have been characterized by elemental analysis, H-1 NMR and IR spectroscopy. The electron-withdrawing groups on the cyclopentadienyl rings greatly decrease the nucleophilicity of the metallic anions. Thus, only one halogen atom on tin was replaced by the metallic anion when the dianions reacted with SnR2X2. The crystal structures of complexes 4 (M = Mo; R = Me; X = Cl; n = 2) and 5 (M = W; R = Ph; n = 3) were determined by X-ray crystallography, indicating that both Mo and W atoms adopt a 3:4 piano stool structure, and the Sn-M bond length is 2.7755(3) Angstrom in complex 4 (Sn-Mo) and 2.8154(7) Angstrom in complex 5 (Sn-W). (C) 2001 Elsevier Science B.V. All rights reserved.