Diazomethylphosphine Oxides

Abstract

Z-Metltyl-Z-benzoyl-1,3-ditf1icme (5d):To a cold (-78'C) solution of 10 mmoles of the iithium derivative ( I ) , RI=CH3, in tetrahydrofuran 111 was added with stirring 1.06 g (10 mmoles) of benzonitrile. The resulting bright orange mixture was kept at -78 O C for 40 min, after which the bath was removed and stirring was continued for an additional 40 min. The reaction mixture was then poured onto ice and extracted with ether. The extracts were washed with dilute base, dried over NazS04 and concentrated to give 2.22 g (95%) of crude imine which was hydroiysed with 150 ml of 4 "/, hydrochloric acid at 7OoC for 45 min. The product, which partially separated as colorless crystals, was removed by extraction with ether. After washing, drying, and concentration the extract yielded 1.95 g (82 x) of (5d), m.p. 97.8-98.7 "C. After recrystallization from methanol the m.p. is 98.4-98.8 "C.