Synthesis of Arylglycines by Reaction of Diethyl N-Boc-iminomalonate with Organomagnesium Reagents

Abstract

Diethyl N-Boc-iminomalonate (3), prepared on multi-gram scale, served as a stable and highly reactive electrophilic glycine equivalent which reacted with organomagnesium compounds affording substituted aryl N-Boc-aminomalonates. Subsequent hydrolysis produced arylglycines.

Key words

amino acids - arylaminomalonates - arylglycines - imino esters - Grignard reactions

References

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16

As described in the experimental section, the best results were obtained by using 1.1 equivalents of iminomalonate 3 to drive the Grignard reaction to completion. However, the use of larger excess resulted in troublesome purification.