Alkyl Ethers of Alpha-Amino Oxime of the Pinane Series as a Platform for the Synthesis of Highly Lipophilic Alpha-Aminophosphonates

A method to synthesis new hybrid derivatives of α-pinene with α-aminophosphonate fragment has been developed to obtain an additional centre of metal coordination in the molecules of potential extractants for heavy metals. It has been shown that O-alkyl ethers of a-amino oximes of the pinane series can be converted according to the two-stage version of Kabachnik-Fields reaction with dimethylphosphite and benzaldehyde into new chiral α-aminophosphonates with a satisfactory preparative yield (40-42 %). According to this scheme, terpene aminophosphonates are obtained as highly lipophilic products in the form of a pair of stereoisomers with a diastereomeric purity of 49-66 %.