反应详情

Process 2: 8.5 g. (0.03 mole) of N-(3-metoxycarbonyl-5-nitrobenzoyl-glycine (VIa) dissolved in 130 ml. of absolute tetrahydrofuran, is cooled to -15° C., after the addition of 4.2 ml. of triethylamine, and mixed under agitation with 3 ml. of the ethyl ester of chlorocarbonic acid. The reaction mixture is agitated for about 10 minutes at -10° to -5° C., and a solution of 2.8 ml. of methylamine in 20 ml. of absolute tetrahydrofuran, cooled to -15° C., is gradually added thereto dropwise under agitation. Then, the mixture is stirred for another 30 minutes at -15° C. and subsequently overnight at room temperature; the triethylamine hydrochloride is filtered off, the filtrate concentrated under vacuum, and the residue recrystallized from acetonitrile; yield 4.6 g. m.p. 173°-174° C.

1. additionafter the addition of 4.2 ml
2. additionis gradually added
3. stirringThen, the mixture is stirred for another 30 minutes at -15° C. and subsequently overnight at room temperature
4. filtrationthe triethylamine hydrochloride is filtered off
5. concentrationthe filtrate concentrated under vacuum
6. customthe residue recrystallized from acetonitrile