Optical resolution of racemic aromatic cpds. - by chromatography on carrier-bound electron acceptor or donor

摘要

Chromatographic resolution of racemic aromatic cpds. uses a stationery phase comprising an optically active electron acceptor (when the aromatic cpd. is an electron donor) or electron donor (when the aromatic cpd. is an acceptor) covalently bonded to carrier. The electron acceptor or donor bonded to the carrier must be capable of forming a charge transfer complex w%having a heat of formation of 0.5-20 kcal/mole with the aromatic cpd. The process can be used to isolate optically active mono- and polynuclear aromatic cpds., including asymmetric aliphatic cpds. into which removable aromatic substituents have been introduced. The stationary phase is more stable than those in which the carrier is simply impregnated with the electron acceptor or donor. In an example, racemic ethyl alpha-(N-carbazolyl)propionate is resolved on a column packed with the reaction product of NH2-modified silica gel and (-)-alpha-(2,4,5,7-tetranitro-9-fluorenylidenaminooxy)-propionyl chloride.