Experimental and Computational Study of Auxiliary Molecular Effects on the Mechanism of the Addition of Hydrazines to a Low-Valent Germanium Complex

Reaction of the diarylgermylene Ge­(ArMe6)2 (ArMe6 = C6H3-2,6-(C6H2-2,4,6-(CH3)3)2) with hydrazine and methylhydrazine gave the
first
structurally characterized Ge­(IV) hydrazide complexes, (ArMe6)2Ge­(H)­NHNHR (R = H, Me). A detailed computational
study of the mechanism of this N–H bond activation showed that
the reaction proceeds via an intermolecular proton transfer, which
is mediated by a second equivalent of hydrazine that interacts with
the hydrazine–Ge­(ArMe6)2 adduct
intermediate through N- - -H hydrogen bonding. This
auxiliary effect is blocked when the substituted derivative N,N-dimethylhydrazine is used, and a Lewis
adduct complex of Ge­(ArMe6)2 is the
only product obtained.