The formation of C-N bonds for the preparation of amines compounds is a reaction of high
relevance for the synthesis of bulk and fine chemicals (1). The preparation of several drug
molecules involves N-substitution transformations that are usually performed by reaction of
amines with alkylating agents or via reductive amination. In this context, the catalytic Nalkylation
of amines using environmentally friendly alcohols as alkylating reagents and
affording water as only byproduct, is an attractive atom-economic way for the C-N bond
formation (2,3).
We report here the straightforward synthesis of the carboxylate ruthenium complexes
of formula Ru(OAc)2(diphosphane)(CO)n (n = 0, 1). These compounds are efficient catalysts
for the N-alkylation of amines using primary alcohols under mild reaction conditions, with an
alcohol / amine molar ratio of 10-100. Evidence has been provided that in catalysis a
monohydride species is formed through an equilibrium reaction.
