Straightforward Synthesis of 1-Amino-2,2-dialkylcyclopropanecarboxylic Acids via Selective Saponification of 2,2-Dialkylcyclopropane-1,1-dicarboxylic Esters and Curtius Rearrangement

Article abstract of DOI:10.1021/jo00105a045

Selective monosaponification of dimethyl 2,2-dialkylcyclopropane-1,1-dicarboxylic esters afforded the corresponding 2,2-dialkyl-1-(methoxycarbonyl)cyclopropane-1-carboxylic acids, which were rearranged with diphenyl phosphoroazidate via a modified Curtius-type reaction to give methyl 2,2-dialkyl-1-cyclopropanecarboxylic esters.Selective deprotection of the carbamate or methyl cyclopropanecarboxylic ester was worked out, giving rise to a whole variety of ACC analogues.Straightforward ways to 1-amino-2,2-dialkylcyclopropanecarboxylic acids (2,2-dialkyl-ACC's) were developed.