Acyclic and cyclic aminophosphonic acids: asymmetric syntheses mediated by chiral sulfinyl auxiliary

Aminophosphonic acids have become increasingly important in different fields of chemistry, medicine and agriculture. This account outlines the results obtained in the author’s laboratory on the asymmetric synthesis of acyclic and cyclic aminophosphonic acids mediated by chiral sulfinyl auxiliary. A key reaction in the synthesis of enantiopure α- and β-aminoalkanephosphonic acids involving a highly diastereoselective addition of phosphite anions or α-phosphonate carbanions to enantiopure sulfinimines is discussed. The asymmetric cyclopropanation of enantiopure α-phosphorylvinyl sulfoxides with sulfur ylides is presented as a platform for developing a new approach to optically active β-aminocyclopropanephosphonic acids. It is exemplified by the total synthesis of enantiopure β-amino-γ-phenylcyclopropanephosphonic acid - a constrained analogue of the GABA_B antagonist phaclofen.