Methanol → HCID 131712716, compound

Participants

Reaction Steps

To a solution of 387 g (0.906 mole) of (±)-1-cyclopropylmethyl-4-(3-trifluoromethylthio-5H-dibenzo[a,d]cyclohepten-5-ylidene)piperidine (I) in 3870 ml of toluene containing 19 ml of methanol at room temperature (22°) was added 220 g (0.569 mole) of di-p-toluoyl-d-tartaric acid. A complete solution resulted within three minutes followed by rapid crystallization of the desired tartrate salt. The mixture was stirred vigorously at room temperature (23°) overnight. The crystalline product was collected by filtration, washed with 1 l. of toluene and dried under vacuum at room temperature to yield 355 g (86.5% physical yield) of (-)-1-cyclopropylmethyl-4-(3-trifluoromethylthio-5H-dibenzo[a,d]-cyclohepten-5-ylidene)piperidine di-p-toluoyl-d-tartrate, as the toluene solvate (II), m.p. 142°-146° dec., [α]D25 -91.3° (C=1, EtOH). A sample of this salt was converted to the free base and had a m.p. of 142°-145° dec., [α]D25 -58.0° (C=1, CH2Cl2) indicating 87% optical purity (O.P.).

Provenance & Evidence