Reactions of [(dmpe) 2 MnH(C 2 H 4 )]: synthesis and characterization of manganese( i ) borohydride and hydride complexes

Reactions of trans-[(dmpe)₂MnH(C₂H₄)] (1) with BH₃(NMe₃), 9-BBN, and HBMes₂ yielded the manganese(i) borohydride complexes [(dmpe)₂Mn(μ-H)₂BR₂] (3: R = H, 4: R₂ = C₈H₁₄, 5: R = Mes). The reaction of 1 with BH₃(NMe₃) proceeds via ethylene substitution. By contrast, a detuerium labelling study indicates that the reaction of 1 with HBMes₂ involves initial isomerization of 1 to an unobserved 5-coordinate ethyl intermediate, [(dmpe)₂MnEt], which …