Diphosphine as an overhead bridge across a heterometallic M-M ' bond. A flexible cluster system in (P-P)AuMn2(CO)(mu-PPh2) that accommodates all common diphosphines

The inter-triangular diphosphine bridge in [AuMn2(CO)(8)(mu -PPh2)](2)(mu - P-P) turns into an intra-triangular one as it undergoes amine-oxide-promote d decarbonylation to give (P-P)-AuMn2(CO) (7)(mu -PPh2) (P-P = Ph2P-X-PPh2; X = (CH2)(n), Fe(C5H4)(2); n = 1-4) in the presence of the corresponding f ree diphosphine. The resultant triangular cluster contains a heterometallic Au-Mn bond overbridged by all common diphosphines attempted, including dpp f(X = Fe(C5H4)(2)) and dppp (n = 3). The Au-Mn bond supported by dppf (2.67 97(7) Angstrom) is shorter than that supported by dppe (n = 2) (2.756(2) An gstrom) or dppp (2.7643(4) Angstrom).