Facile Routes to Manganese(II) Triflate Complexes

Manganese(II) chloride reacts with trimethylsilyl triflate (TMS(OTf) where OTf = (-)OSO(2)CF(3)) in a 1:1 mixture of acetonitrile and tetrahydrofuran, and after recrystallization affords the linear coordination polymer Mn(II)(CH(3)CN)(2)(OTf)(2)](n). Each distorted octahedral manganese(II) center in the polymeric chain has trans-acetonitriles and the remaining equatorial coordination positions are occupied by the bridging triflate anions. Dissolving Mn(II)(CH(3)CN)(2)(OTf)(2)](n) in equal volumes of acetonitrile and pyridine followed by recrystallization with diethyl ether yields trans-Mn(II)(C(5)H(5)N)(4)(OTf)(2)]. The distorted octahedral geometry of the manganese center features monodentate trans-triflate anions and four equatorial pyridines. Exposure of either Mn(II)(CH(3)CN)(2)(OTf)(2)](n) or Mn(II)(C(5)H(5)N)(4)(OTf)(2)] to water readily gives Mn(II)(H(2)O)(6)](OTf)(2). XRD reveals hydrogen-bonding interactions between the Mn(II)(H(2)O)(6)](2+) cation and the triflate anion. All three of these species are easily crystallized and provide convenient sources of manganese(II) for further synthetic elaboration.