The effect of substituents on the extraction behavior of hydroxamic acids

The extraction behavior of several alkyl-substituted hydroxamic acids in chloroform solution with several metal ions is described. Among the N-phenylacylhydroxamic acids used, those with o-alkyl substituents on either the phenyl or acyl ring generally do not extract metals, apparently because of steric problems at the O=CNO^? chelation site. An improved synthesis of substituted hydroxamic acids is reported.