反应详情

温度

0 °C

4.43 g (0.028 mole) of (+)-menthol and 0.34 g (0.003 mole) of 4-dimethylaminopyridine are added to a solution of 5.0 g (0.028 mole) of (E)-4-oxo-4-phenyl-2-butenoic acid in 60 ml of anhydrous dichloromethane. After cooling the solution to 0° C., a solution of 5.86 g (0.028 mole) of N,N-dicyclohexylcarbodiimide in 20 ml of anhydrous dichloromethane is added. The mixture is stirred at 0° C. for 30 minutes, then at room temperature for one hour. The reaction mixture is worked up as described in Example 1 to give the crude product as a dark-brown oil in a yield of 8.1 g (91%) which is purified by using column chromatography as described in Example 1. The named compound is obtained in a yield of 6.7 g, Rf =0.78 (dichloromethane); [α]D25 =+65° (c=2.0, chloroform).

1. waitat room temperature for one hour
2. customto give the crude product as a dark-brown oil in a yield of 8.1 g (91%) which
3. customis purified
4. customThe named compound is obtained in a yield of 6.7 g, Rf =0.78 (dichloromethane)