反应详情

N-methyl-N-[(phenylmethoxy)carbonyl]glycine (2.23 g., 10 mmole) is dissolved in 30 ml. of tetrahydrofuran and cooled in an ice-bath. Oxalyl chloride (1 ml., 11.5 mmole) is added followed by 2 drops of dimethylformamide. After stirring for 30 minutes in the ice-bath, the mixture is then stirred at room temperature for an hour. To this 0.25 ml. of oxalyl chloride is added. The mixture is evaporated, redissolved in 15 ml. of tetrahydrofuran, and stirred in an ice bath. A solution of 2-phenyl-4-(phenylmethyl)-5(4H)-oxazolone (3.1 g., 12.4 mmole) dissolved in 15 ml. of tetrahydrofuran is added to the above solution stirring in the ice-bath. Triethylamine (1.4 ml., 10 mmole) is added and the solution is stirred at room temperature overnight. The precipitated triethylamine hydrochloride salt is filtered off. Tetrahydrofuran is removed from the residue and it is then redissolved in pyridine (5 ml.) and p-dimethylamino pyridine (20 mg.) is added. After stirring at room temperature for 3 hours, acetic acid (5 ml.) is added and the reaction mixture is kept at 105° for 30 minutes. The reaction mixture is then evaporated, the residue is dissolved in ethyl acetate, and washed with aqueous sodium bicarbonate and water. After trituration with ethyl acetate/hexane, 2.2 g. of homogeneous [3-(benzoylamino)-2-oxo-4-phenylbutyl]methylcarbamic acid, phenylmethyl ester is obtained; m.p. 140°-141°.

1. customThe mixture is evaporated
2. dissolutionredissolved in 15 ml
3. stirringof tetrahydrofuran, and stirred in an ice bath
4. stirringthe solution is stirred at room temperature overnight
5. filtrationThe precipitated triethylamine hydrochloride salt is filtered off
6. customTetrahydrofuran is removed from the residue and it
7. dissolutionis then redissolved in pyridine (5 ml.)
8. additionp-dimethylamino pyridine (20 mg.) is added
9. stirringAfter stirring at room temperature for 3 hours
10. additionacetic acid (5 ml.) is added
11. customThe reaction mixture is then evaporated
12. dissolutionthe residue is dissolved in ethyl acetate
13. washwashed with aqueous sodium bicarbonate and water