Übergangsmetall-carbin-komplexe: LXXXIII. Neue anionische mer-dihalogeno-tricarbonyl-dialkylamino-carbin-komplexe des wolframs

Abstract

The reaction of trans-X(CO) 4WCNR 2 (X = Br, R = c hex (cyclohexyl); X = Cl, R = c hex, ipr (isopropyl) with M +X − (M + = NEt 4 +, X − = Br −; M + = PPN +, X − = Cl −) leads under substitution of one CO ligand to new anionic dihalo(tricarbonyl)carbyne-tungsten complexes of the type M + mer-[(X) 2(CO) 3WCNR 2] − (M + = NEt 4 +, X = Br, R = c hex; M + = PPN +, X = Cl, R = c hex, i pr), whose composition and structure were determined by elemental analysis as well as by IR, 1H and 13C NMR spectroscopy. In the anionic carbyne complexes the entered halogen ligand, coordinated in a cis position relative to the carbyne ligand on the metal, can be easily substituted by neutral nucleophiles, as the reaction of PPN + mer-[(Cl) 2(CO) 3WCN chex 2] − with PPh 3 demonstrates yielding the neutral carbyne complex mer-[Cl(CO) 3(PPh 3)WCN chex 2].