Coordination chemistry of the cyclo-(P(5)tBu(4))(-) ion: monomeric and oligomeric copper(I), silver(I) and gold(I) complexes

Na{cyclo-(P(5)tBu(4))}] (1) reacts with CuCl(PCyp(3))(2)] (Cyp=cyclo-C(5)H(9)) and CuCl(PPh(3))(3)] (1:1) to give the corresponding copper(I) complexes with a tetra-tert-butylcyclopentaphosphanide ligand, Cu{cyclo- (P(5)tBu(4))}(PCyp(3))(2)] (2) and Cu{cyclo-(P(5)tBu(4))}(PPh(3))(2)] (3). The CuCl adduct of 2, Cu(2)(mu-Cl){cyclo-(P(5)tBu(4))}(PCyp(3))(2)] (4), was obtained from the reaction of 1 with CuCl(PCyp(3))(2)] (1:2). Compounds 2 and 3 rearrange, even at -27 degrees C, to give Cu(4){cyclo- (P(4)tBu(3))PtBu}(4)] (5), in which ring contraction of the cyclo-(P(5)tBu(4))](-) anion has occurred. The reaction of 1 with AgCl(PCyp(3))](4) or AgCl(PPh(3))(2)] (1:1) leads to the formation of Ag(4){cyclo-(P(4)tBu(3))PtBu}(4)] (6). Intermediates, which are most probably mononuclear, "Ag{cyclo-(P(5)tBu(4))}(PR(3))(2)]" (R=Cyp, Ph) could be detected in the reaction mixtures, but not isolated. Finally, the reaction of 1 with AuCl(PCyp(3))] (1:1) yielded Au{cyclo-(P(5)tBu(4))}(PCyp(3))] (7), whereas an inseparable mixture of Au(3){cyclo-(P(5)tBu(4))}(3)] (8) and Au(4){cyclo-(P(4)tBu(3))PtBu}(4)] (9) was obtained from the analogous reaction with AuCl(PPh(3))]. Complexes 3-7 were characterised by (31)P NMR spectroscopy, and X-ray crystal structures were determined for 3-9.