A preparative procedure is proposed for the synthesis of α-aminophosphonates of natural porphyrins by the microwave-assisted Kabachnik—Fields reaction.

The reaction of diethyl phosphonate with Schiff bases derived from aldehydes and ketones in the presence of cadmium iodide is strongly accelerated by microwave irradiation, and the corresponding α-aminophosphonates are formed in high yields.

The first synthesis of α-amino phosphonates comprising porphyrin core was accomplished. Three methods of obtaining α-amino phosphonates 5-8 were compared. Conventional heating of formylporphyrins 1-4 with t-BuNH 2 and (EtO) 2 P(O)H in various solvents was ultimately unsuccessful for preparing 5-8 whereas the use of microwave irradiation made it possible to obtain 5-8 in good yields. Regioselective preparation of 5-8 in excellent yields was achieved by combining microwave-assisting conditions and catalysis with CdI 2 . Efficient synthetic procedures of obtaining formylporphyrins 3,4 in large scale were also proposed.

An easy preparative synthesis of α-aminophosphonates by reaction of azomethines with diethyl phosphite under conditions of phase-transfer catalysis was developed.

The reaction of hydrophosphoryl compounds with aldimines and ketimines in the presence of catalytic amounts of cadmium iodide was investigated. A simple preparative method for the synthesis of α-aminophosphonates, phosphinates, and tertiary phosphine oxides was developed.