HCID 10547933, compound → HCID 70102228, compound

Participants

Reaction Conditions

Reaction Steps

Borane-dimethyl sulphide complex (1M solution in dimethyl sulphide; 0.5 ml) was added dropwise under nitrogen to a solution of 1-(1,4-benzodioxan-2-ylmethyl)-N-(2-methoxyphenyl)piperidine-4-carboxamide (0.35 g) in dry tetrahydrofuran (25 ml) and then the mixture was heated under reflux for 2 hours. The reaction was cooled and the solvents removed in vacuo. The residue was diluted cautiously with dilute hydrochloric acid (1M; 70 ml) and heated at 95° C. for 1.5 hours. The aqueous mixture was cooled and basified by the addition of aqueous sodium hydroxide solution (2.5M), there the product was extracted into dichloromethane. The organic extract was washed with water, then dried over magnesium sulphate, filtered, and the solvent removed in vacuo to yield 1-[1-(1,4-benzodioxan-2-ylmethyl)piperid-4-yl]-N-(2-methoxyphenyl) methylamine (0.32 g). The procedure was repeated using 1-(1,4-benzodioxan-2-ylmethyl)-N-(2-methoxyphenyl)piperidine-4-carboxamide (1.37 g, prepared in a similar manner to that described above). The products of the two reactions were combined and dissolved in ether. Hydrogen chloride was bubbled through the solution and the resulting solid precipitate collected by filtration (1.2 g). The solid was dissolved in saturated aqueous sodium hydrogen carbonate solution (100 ml) and the resulting oil extracted into ethyl acetate (100 ml). An excess of a saturated solution of oxalic acid in ethyl acetate was added and the solid precipitate was collected by filtration and dried in vacuo at 50° C. to yield 1-[1-(1,4-benzodioxan-2-ylmethyl) piperid-4-yl]-N-(2-methoxyphenyl)methylamine mono-oxalate (0.78 g), m.p. 215°-218° C.

Provenance & Evidence