Chemoselective addition of organometallics to oxime ethers

An efficient method for preparation of substitued hydroxylamines from aldehydes is reported. First O-trimethylsilyl oxime ether prepared from condensation reaction between aldehyde and O-trimethylsilyl hydroxylamine, then added organosilane or organotin nucleophile in the same vessel to preparing the corresponding α-substituted hydroxylamines in one-pot and chemoselective synthesis.