A New, General Entry to 3,5-Unsubstituted 4-O-Alkyl Tetramates

Abstract

A variety of 3,5-unsubstituted 4-O-benzyl tetramates 10 was prepared in good overall yield from methyl (E)-3-benzyloxy-4-oxobut-2-enoate 7 by a reductive amination-lactamization sequence. An efficient approach to this building block as well as to various 3-alkoxy analogues is presented.

Key words

tetramic acids - enols - conjugate additions - aminations - lactams

References and Notes

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