Synthesis, reactivity, and structures of (mu-acetamidato)hexakis(acetonitrilo)dimolybdenum(II) tris(tetrafluoroborate) and derivatives

Reaction of [Mo-2(CH3CN)(8)](BF4)(4) (1) with the stoichiometric amount of acetamide leads to the violet, moisture sensitive complex [Mo-2(mu-CH3CONH) (CH3CN)(6)](BF4)(3) (2). Reaction of the latter compound with two equivalen ts of dppm yields the purple [Mo-2(mu-CH3CONH)(mu-dppm)(2)(CH3CN)(2)](BF4)( 3) (3). Compound 2 can also be prepared by reacting 1 with H2O in acetonitr ile. Reaction of 1 with toluidine leads to a compound of composition [Imidi nium] [Mo-2(mu-(HNC(CH3)-N(C7H7))(CH3CN)(6)](BF4)(4) (4), and reaction with pyridine in the presence of water yields [Mo-2(mu-CH3CONH)(NC5-H-5)(5) (OH )](BF4)(2) (5). All these latter reactions are driven by the high electroph ilicity of the [Mo-2](4+) core which makes the coordinated nitrile ligands highly susceptible to nucleophilic attack. (C) 1999 Elsevier Science S.A. A ll rights reserved.