Hydrogen chloride-ethyl acetate → 1-(2,4-Dimethylphenyl)-[1,4]diazepane hydrochloride

Participants

Reaction Steps

To a mixture of 1-bromo-2,4-dimethylbenzene (1.85 g), 1-Boc-[1,4]diazepane (2 g), palladium(II) acetate (0.12 g), rac-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (0.31 g) and sodium tert-butoxide (1.34 g) was added toluene (35 mL), and the mixture was stirred with heating under reflux for 9 hr. Water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine, and the solvent was evaporated. The obtained residue was purified by column chromatography (chloroform:methanol) to give 4-(2,4-dimethylphenyl)-[1,4]diazepane-1-carboxylic acid tert-butyl ester (2.16 g). The obtained 4-(2,4-dimethylphenyl)-[1,4]diazepane-1-carboxylic acid tert-butyl ester (2.16 g) was dissolved in chloroform (17 mL), 4N hydrogen chloride/ethyl acetate solution (6.9 mL) was added, and the mixture was stirred at room temperature overnight. The solvent was evaporated from the reaction mixture to give the title compound (1.74 g).

Provenance & Evidence