摘要:
The cationic complexes fac-[Mn(CNBut)(CO)3(dppm)]ClO4 (1a) and [Mn(CO)4(dPPM)]ClO4 (1b) are readily deprotonated by KOH in CH2Cl2 to give the bis(diphenylphosphino)methanide derivatives fac-[Mn(CNBut)(CO)3{(Ph2P)2CH}] (2a) and [Mn(CO)4{(Ph2P)2CH}] (2b). When 2a and 2b are reacted with [Ag(ClO4)(PPh3)], the heterodimetallic complexes fac-[Mn(CNBut)(CO)3{(Ph2P)2CH(AgPPh3)}]ClO4 (3a) and [Mn(CO)4{(Ph2P)2CH(AgPPh3)}]ClO4 (3b) are obtained. For 3a an X-ray analysis has been carried out. Crystal data: monoclinic, space group P2(1)/c, a = 11.828 (3) angstrom, b = 24.518 (5) angstrom, c = 17.293 (6) angstrom, beta = 94.94 (3)-degrees, V = 4996 (2) angstrom3, Z = 4, R = 0.033, R(w) = 0.036. The heterodimetallic complexes [Mn-(CNBut)(CO)3{(Ph2P)2CH(AuPPh3)}]ClO4 (4a) and [Mn(CO)4{(Ph2P)2CH(AuPPh3)}]ClO4 (4b) have been synthesized by two alternative methods: (a) by treating 1a and 1b with 1 equiv of [AuCI(PPh3)] and an excess of KOH and (b) by reacting 3a and 3b with 1 equiv of [AuCl(PPh3)]. The treatment of 1a and lb with 2 equiv of [AuCI(PPh3)] and an excess of KOH produces the trimetallic species fac-[Mn(CNBut)-(CO)3{(Ph2P)2C(AuPPh3)2}]ClO4 (5a) and [Mn(CO)4{(Ph2P)2C(AuPPh3)2}] (5b), which formally contain the dianion [(PPh2)2C]2-. When 4a is reacted with [AgCl(PPh3)], in the presence of KOH, the mixed heterotrimetallic species [Mn(CNBut)(CO)3{(Ph2P)2C(AgPPh3)(AuPPh3)}]ClO4 (6a) is obtained. A mechanism for the formation of 6a involving the neutral intermediate [Mn(CNBut)(CO)3{(Ph2P)2C(AuPPh3)}] (7) is proposed in agreement with the data obtained in the X-ray analysis of 6a. Crystal data: monoclinic, space group P2(1)/n, a = 14.192 (3) angstrom b = 20.622 (6) angstrom, c = 24.37 (1) angstrom, 94.91 (3)-degrees, V = 7106 (5) angstrom3, Z = 4, R = 0.045, R(w) = 0.044.