A One-Pot Aza-Wittig Based Solution and Polymer Supported Route to Amines

This paper presents a high yielding one-pot solution phase and polymer supported synthesis of a range of primary and secondary amines starting from azides and aldehydes. The synthesis utilises a tandem process which begins with an aza-Wittig reaction between the aldehyde and an iminophosphorane, followed by reduction, or organometallic 1,2-addition reaction, of the resultant imine. The requisite iminophosphoranes were accessed using the highly efficient Staudinger reaction between the azide starting material and a phosphine. The process was applicable to the solid phase by the use of polymer supported iminophosphoranes and polymer supported cyanoborohydride.