Simultaneous Resolution of Clenbuterol Hydrochloride Enantiomers and Propranolol Hydrochloride Enantiomers using Thin-Layer Chromatography

Resolution of clenbuterol hydrochloride enantiomers and propranolol hydrochloride enantiomers was achieved by thin-layer chromatography using methyl-beta-cyclodextrin impregnated silica gel GF254 plates. The effects of stereoselective auxiliary (acetonitrile/different alcohols) were studied. Resolution of clenbuterol hydrochloride enantiomers could be realized by alcohols such as ethanol, n-butanol, 2-butanol or tert-butanol together with acetonitrile, and propranolol hydrochloride enantiomers could only be resoluted by ethanol or n-butanol together with acetonitrile. The optical conditions of simultaneous resolution were obtained as follows: 15.00g silica gel GF254 plates impregnated with 1.00g methyl-beta-cyclodextrin, acetonitrile/n-butanol (VN = 90:10) mixed solvent as spreading solvent, being resolved under ambient temperature. Under these conditions, R-F value of resolution of clenbuterol hydrochloride enantiomers is 3.47, R-F value of resolution of propranolol hydrochloride enantiomers is 3.35. The two couples of enantiomers were all achieved base line separation.