625830-77-5Relevant articles and documents
Manganese-gold and -silver mixed-metal clusters derived from the unsaturated binuclear complex [Mn2(CO)6 (μ-Ph2PCH2PPh2)]2-(Mn=Mn) and related anions
Liu, Xiang-Yang,Riera, Victor,Ruiz, Miguel A.,Lanfranchi, Maurizio,Tiripicchio, Antonio
, p. 4500 - 4510 (2008/10/08)
Reaction of the unsaturated dihydride [Mn2(μ-H)2(CO)6(μ-dppm)] with Li[BHEt3] proceeds stepwise, giving first the anionic hydride [Mn2(μ-H)(CO)6(μ-dppm)]- and then the dianion [Mn2(CO)6(μ-dppm)]2-, both having a formally double metal-metal bond. In contrast, reaction with Na[BH4] gives cleanly the fluxional anionic trihydride [Mn2(μ-H)H2(CO)6(μ-dppm)]-, which is electron precise. A related electron-precise dianion, [Mn2(CO)8(μ-dppm)]2-, is readily prepared by reducing [Mn2(CO)8(μ-dppm)] with Na amalgam and is protonated by [NH4]PF6 to give the corresponding dihydride [Mn2H2(CO)8(μ-dppm)]. The unsaturated anions react cleanly with silver or gold complexes of the type [MCl(PR3)] (M = Ag, R = Cy; M = Au, R = Ph, p-tol) to give the corresponding trinuclear hydride clusters [Mn2M(μ-H)(CO)6(μ-dppm)(PR3)] or the tetranuclear clusters [Mn2M2(CO)6(μ-dppm) (PR3)2] (X-ray study for M = Au, R = p-tol). The trinuclear manganese-gold cluster adds CO easily to give the electron-precise [Mn2Au(μ-H)(CO)7(μ-dppm){P(p-tol)3}], but the tetranuclear clusters react with simple donors in a more complex way. For example, reaction with (EtO)2POP(OEt)2 (tedip) gives a mixture of the corresponding tetranuclear derivatives [Mn2Au2(CO)5(μ-dppm)(PR3)(μ-te dip)], arising from substitution of peripheral CO and PR3 ligands, and the trinuclear alkoxyphosphido clusters [Mn2Au{μ-P(OEt)2}(CO)6(μ-dppm) (PR3)], derived from the cleavage of a P-O bond in the backbone of the diphosphite ligand. The acid-base behavior of the tetranuclear digold clusters has been further explored through the reaction with HBF4·OEt2, which gives the cationic hydride cluster [Mn2Au2(μ3-H)(CO)6(μ-dppm){P(p - tol)3}2]BF4, and the reaction with SnCl2, which gives the raft-type pentanuclear manganese-gold-tin cluster [Mn2Au2SnCl2(CO)6(μ-dppm) {P(p-tol)3}2], characterized through an X-ray study.
