The Preparation and Coordination Chemistry of Phosphorus(III) Derivatives of piperazine and Homopiperazine

Reaction of piperazine or homopiperazine with R2PCl [R-2 = Ph-2, OC2H4O, OC6H4O] gives six new bidentate phosphines. Simple bis-chelate and bridging complexes with demonstrative Mo(0), Pd(II), Pt(II) and Ru(II) centres are reported. The crystal structures of Ph2P(O)N(C2H4)(2)P(O)Ph-2, cis-[PdCl2{Ph2PN(C2H4)(2)NPPh2}] (7) and cis -[PtCl2{Ph2PN(C5H10)NPPh2}][PtcodCl(2)](2) (15) are reported. In Ph2P(O)N(C2H4)(2)P(O)Ph-2 the central N2C4 ring has a chair conformation and the P=O groups are trans. In 7 the piperazine backbone results in P-Pd-P bite angle of approximately 95degrees whilst in 15 the homopiperazine backbone enlarges the bite angle to 97degrees. (C) 2002 Elsevier Science Ltd. All rights reserved.