Formaldehyde → 8-Chloro-5-methyl-1-(3,4,5,6-tetrahydro-2h-[1,2']bipyridinyl-4-yl)-5,6-dihydro-4h-2,3,5,10b-tetraaza-benzo[e]azulene trihydrochloride

Participants

Reaction Steps

Formaldehyde (37% w/v aqueous, 0.1 ml, 1.2 mmol) was added to a solution of the amine of example 4 (200 mg, 0.53 mmol) in dichloromethane (5 ml). The mixture was stirred at room temperature for 0.25 hours before sodium triacetoxyborohydride (500 mg, 2.4 mmol) was added, and the reaction mixture was stirred for a further 18 hours. The reaction mixture was partitioned between 2N aqueous sodium hydroxide solution (10 ml) and dichloromethane (10 ml). The organic layer was evaporated under reduced pressure and purified by chromatography on silica gel using methanol in dichloromethane (5:95) as eluant. The residue was dissolved in dichloromethane (2 ml) and hydrochloric acid (1M in diethyl ether, 2 ml) was added. The solvent was evaporated under reduced pressure to give the title compound as a brown foam (96 mg).

Provenance & Evidence