反应详情

温度

0 °C

1 g of triethylamine is added to 2.7 g of 5-chloro-2-hexahydrobenzyloxy-nicotinic acid (melting point 150° to 151° C., prepared from 2-chloronicotinic acid by reacting same with hexahydrobenzyl alcohol-sodium with subsequent chlorination with chlorine) in 100 ml of tetrahydrofuran and, after cooling to 0° C., 0.95 g of chloroformic acid methyl ester is added. Stirring of the mixture is continued for 15 minutes at 0° C. and the mixture is added to 10 ml of an about 1 molar solution of 4-(2-aminoethyl)-benzoic acid sodium additionally containing 0.01 mol of sodium acetate, and stirring is continued for 3 hours at room temperature. The major proportion of the solvent is distilled off under reduced pressure and the residue is acidified. The 4-(2-<5-chloro-2-hexahydrobenzyloxy-nicotinamido>-ethyl)-benzoic acid obtained is reprecipitated from ammonia and recrystallized from dilute ethanol. Melting point 177°-178° C.

1. stirringstirring
2. waitis continued for 3 hours at room temperature
3. distillationThe major proportion of the solvent is distilled off under reduced pressure