STRAIGHTFORWARD SYNTHESIS OF 1-AMINO-2,2-DIALKYLCYCLOPROPANECARBOXYLIC ACIDS VIA SELECTIVE SAPONIFICATION OF 2,2-DIALKYLCYCLTOPROPANE-1,1-DICARBOXYLIC ESTERS AND CURTIUS REARRANGEMENT

Selective monosaponification of dimethyl 2,2-dialkylcyclopropane-1,1l- dicarboxylic esters afforded the corresponding alkyl-1-(methoxycarbony l)cyclopropane-1-carboxylic acids, which were rearranged with diphenyl phosphoroazidate via a modified Curtius-type reaction to give methyl -1-[N-(alkoxycarbonyl)amino]cyclopropanecarboxylic esters. Selective d eprotection of the carbamate or methyl cyclopropanecarboxylic ester wa s worked out, giving rise to a whole variety of ACC analogues. Straigh tforward ways to 1-amino-2,2-dialkylcyclopropanecarboxylic acids (2,2- dialkyl-ACC's) were developed.