Preparation and X-ray structures of Cu(I), Ni(II), and Pd(II) (N,S) complexes of the monoanion [((BuN)-Bu-t)(S)P(mu-(NBu)-Bu-t)(2)P(S)((NHBu)-Bu-t)](-) and a Pt(II) (S,S ') complex of the dianion [((BuN)-Bu-t)(S)P(mu-(NBu)-Bu-t)(2)P(S)((NBu)-Bu-t)](2-)

The metathetical reactions of the lithium derivative of the monoanion [((Bu N)-Bu-t)(S)P(mu -(NBu)-Bu-t)(2)P(S)((NHBu)-Bu-t)(-) (L) with CuCl/PPh3, NiC l2(PEt3)(2), PdCl2L'(2) (L' = PhCN, PPh3), and PtCl2(PEt3)(2) produced the complexes (PPh3)-CuL (5), NiL2 (6), PdCl(L)(PPh3) (7), PdL2 (8), and Pt(PEt 3)(2)[((BuN)-Bu-t)(S)P(mu -(NBu)-Bu-t)(2)P(S)((NBu)-Bu-t)] (9). The X-ray s tructures of 5, 6, and 8 reveal a N,S-coordination for the chelating monoan ion L with the metal centers in trigonal planar, tetrahedral, and square pl anar environments, respectively. By contrast, the dianionic ligand in the s quare planar Pt(II) complex 9 is S,S'-chelated to the metal center. P-31 NM R spectra readily distinguish between the N,S and S,S' bonding modes, and, on that basis, N,S chelation is inferred for the Pd(II) complex 7. Crystal data: 5, monoclinic, P2(1)/c, a = 19.175(4) Angstrom, b = 20.331(4) Angstro m, c = 10.017(6) Angstrom, beta = 91.79(3)degrees, V = 3903(2) Angstrom (3) , and Z 4: 6, orthorhombic, Pbcn, a = 14.298(5) Angstrom, b = 15.333(5) Ang strom, c = 24.378(5) Angstrom, beta = 90.000(5)degrees, V= 5344(3) Angstrom (3), and Z = 4: 8. monoclinic. P2(1)/n, a = 13.975(3) Angstrom, b = 14.283 (3) Angstrom, c 15.255(4) Angstrom, beta = 116.565(18)degrees, V = 2723.5(1 1) Angstrom (3), and Z = 2: 9, monoclinic, P2(1)/n, a = 12.479(6) Angstrom, b = 21.782(7) Angstrom, c = 17.048(5) Angstrom, beta = 100.30(3)degrees V = 4559(3) Angstrom (3), and Z = 4.