Benzonitrile → Alpha-benzylaminobenzylphosphonic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of benzonitrile (75g; 0.73 mole) in diethyl phosphite (200g; 1.45 mole) was added W-2 Raney nickel (6g) and the whole mixture charged in an autoclave. The reactor was pressured to 600 psi with hydrogen and the mixture heated to 60° C. The pressure was maintained at 550-600 psi by addition of hydrogen as the reduction proceeded. After 18 hours, uptake of hydrogen had ceased. After cooling hydrogen was released and the catalyst filtered as the reaction product was removed from the reactor. Excess diethyl phosphite and unreacted benzonitrile was removed (135g) by distillation under reduced pressure. The residue was diethyl N-benzyl α-aminobenzylphosphonate. Hydrolysis of this residue with 18% HCl after crystallization yielded N-benzyl α-amino benzylphosphonic acid, 83g (82%), mp 233°-6°. ##STR10##

Provenance & Evidence