Methanol → 1-Cyclohexyl-4-dimethylamino-2-phenyl-2-buten-1-ol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Sodium borohydride (10.3 g) is added over approximately 30 minutes at a temperature in the region of 5° C. to a solution of 2,3-diphenyl-5-methylamino-2,5-dihydrofuran (9.7 g) in methanol (90 cc) and distilled water (10 cc). The reaction mixture is then stirred for 18 hours at a temperature in the region of 20° C., and then concentrated to dryness under reduced pressure (2.7 kPa) at 40° C. The residue obtained is triturated with methylene chloride (100 cc); the suspension obtained is filtered and the filtrate is concentrated to dryness under reduced pressure (2.7 kPa) at 40° C. The residue is purified by chromatography on silica gel (400 g) in a 4 cm diameter column [eluent: methanol/aqueous ammonia (98/2 by volume)]. Elution is first carried out with solvent (400 cc); the corresponding eluate is discarded; elution then continues with solvent (600 cc); the corresponding eluate is concentrated to dryness under reduced pressure (2.7 kPa) at 40° C. The residue obtained is recrystallised from a mixture of hexane (70 cc) and isopropanol (10 cc). In this way 1,2-diphenyl-4-methylamino-2-buten-1-ol (Z) (3.8 g) is obtained in the form of white crystals melting at 90° C.

Herkunft & Nachweise