Ammonia → Methyl 3-(N-phenylamino)-3-phenylpropionate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

At room temperature, a three-neck flask equipped with a reflux condenser, internal thermometer, dropping funnel and stirrer under nitrogen protective gas was initially charged with 7.6 g of zinc powder (116 mmol) in 45 ml of isopropyl acetate. After 1.83 ml of trimethylchlorosilane (14.4 mmol) had been added, the mixture was heated to 60° C. for 15 min, then allowed to cool to 55° C. and 16.3 g of undiluted methyl bromoacetate (107 mmol) were subsequently added dropwise within 5 min, and the temperature was maintained at 60° C. by external cooling. The mixture was then stirred at 50° C. for 15 min. After cooling to 5° C., 16.1 g of benzalaniline (89 mmol) dissolved in 10 ml of isopropyl acetate were added and the mixture was heated to 25° C. After the mixture had been stirred at 25° C. for 1 h, it was heated to 40° C. for a further 10 min and then cooled to 5° C. Hydrolysis was then effected using 80 ml of concentrated ammonia solution. After 40 ml of isopropyl acetate had been added, the mixture was heated to 50° C. and precipitate formed went into solution. At this temperature, excess zinc was filtered off and the organic phase removed. The organic phase was then washed at 50° C. with 20 ml of water. After the phase separation, the solvent was distilled off under reduced pressure to give a crude product in a yield of 19.7 g (87% of theory) and a purity of >95% (HPLC). After recrystallization from ethyl acetate, methyl 3-(N-phenylamino)-3-phenylpropionate having a melting point of 110° C. was obtained.

Herkunft & Nachweise