Complete regioselective addition of grignard reagents to pyrazine N-oxides, toward an efficient enantioselective synthesis of substituted piperazines
(Figure presented) A conceptually new one-pot strategy for the synthesis of protected substituted piperazines via the addition of Grignard reagents to pyrazine N-oxides is presented. This strategy is high yielding (33-91% over three steps), step-efficient, and fast. The synthesized N,N-diprotected piperazines are convenient to handle and allow for orthogonal deprotection at either nitrogen for sel
