Novel Cyclometallated Complexes Derived From a Halogenated Thiosemicarbazone. Crystal and Molecular Structures of 2-FC6H4C(Me)=NN(H)C(=S)NHPh and [(Pd{2-FC6H3C(Me)=NN=C(S)NHPh})2(μ-PPh2(CH2)2PPh2)

Abstract

Treatment of the thiosemicarbazone 2-FC6H4C(Me)= NN(H)C(=S)NHPh, a, with palladium(II) acetate in acetic acid, or with lithium tetrachloropalladate(II) in methanol, gave the tetranuclear cyclometallated complex [Pd{2-FC6H3C(Me)=NN= C(S)NHPh}]4 (1a). Reaction of 1a with the diphosphines Ph2P(CH2) 2PPh2 (dppe), Ph2PCH=CHPPh2 (trans-dpe) Ph2P(CH2)3Ph2 (dppp) or Ph2P(CH2)4Ph2 (dppb) in a 1:2 molar ratio gave the dinuclear cyclometallated complexes [(Pd{2-FC6H 3C(Me)=NN=C(S)NHPh})2(μ-Ph2P(CH 2)nPPh2)], (n = 2, 2a; 3, 4a; 4, 5a) and [(Pd{2-FC6H3C(Me)=NN=C(S)NHPh})2(μ-Ph 2PCH=CHPPh2)], (3a). The X-ray crystal structure of ligand a and of complex 2a are described. The structure of complex 2a shows the palladium atom is bonded to four different donor atoms: C, N, S and P. © 2005 Wiley-VCH Verlag GmbH & Co. KGaA.