反应详情

n-Butyllithium (1.6 M solution in hexane; 11.9 ml; 19 mmol) was added dropwise at 0° C. to a solution of p-tolylamine (1.02 g; 9.5 mmol) in 10 ml THF. The mixture was allowed to come to RT and was subsequently stirred for 1 h. A solution of (4-dimethylamino-4-phenyl-cyclohexyl)-acetic acid ethyl ester (2.5 g; 8.6 mmol) in 15 ml THF was added dropwise at −78° C. The mixture was subsequently stirred for 1 h and then allowed to come to RT. It was hydrolysed with ammonium chloride solution and extracted with MC. After concentration, the crude product was taken up in ether. A solid then remained (less polar diastereoisomer; 1.518 g; 50%); the supernatant was chromatographed on silica gel (eluent:ether, then ether/methanol 4:1). 142 mg (4.7%) of the less polar and 1.20 g (40%) of the more polar diastereoisomer were obtained.

1. customto come to RT
2. stirringThe mixture was subsequently stirred for 1 h
3. customto come to RT
4. extractionextracted with MC
5. concentrationAfter concentration
6. customthe supernatant was chromatographed on silica gel (eluent
7. custom142 mg (4.7%) of the less polar and 1.20 g (40%) of the more polar diastereoisomer were obtained