Synthesis characterisation and stability of mixed aryldichalcogenide bis(diphenylphosphino)ethanenickel(II) complexes. X-ray structure of Ni(dppe)(SeC6H4S)

Mixed chalcogenide complexes of the type Ni(dppe)(SeC6H4S) (dppe=bis(diphen ylphosphino)ethane), Ni(dppe)(SC5H3NCO2) and Ni(dppe)(EC5H3NE') (E=NH, E'=O ; E=E'=NH) have been prepared from the reactions of Ni(dppe)Cl-2 with the a ppropriate aryldichalcogen or pyridine-based compound, using Et3N as a base . The relative solution and thermal stabilities of the above compounds, oth er mixed chalcogen ones, Ni(dppe)(SC6H4O), Ni(dppe)(SC6H4CO2) and Ni(dppe)( SC6H4NH), and the homoleptic compounds Ni(dppe)(EC6H4E') (E=E'=O, E=E'=S; R =H, Me), were established by a combination of electron impact mass spectrom etry (EIMS) and fast atom bombardment (FABMS). The most stable ones were th e compounds with homoleptic sulfur ligands. (C) 1999 Elsevier Science Ltd. All rights reserved.