N~1~-(Pyridin-2-yl)ethane-1,2-diamine → Ethyl 2-[4-[2-(2-pyridylamino)ethylamino]cyclohexyl]acetate

Participants

Reaction Conditions

Reaction Steps

To a mixture of 2-(N-[2-(amino)-ethyl]-amino)-pyridine (685 mg, 5 mmol) and ethyl 2-(4-oxocyclohexyl)acetate (786 mg, 4 mmol) was added dichloromethane (4 mL) followed by titanium ethoxide (420 μL, 2 mmol, technical grade). The resulting mixture was stirred for 4 hr then concentrated under reduced pressure. The residue was taken up in methanol (10 mL) and cooled to −78° C. To this solution was added sodium borohydride (228 mg, 6 mmol). On complete addition, the cold bath was removed and stirring continued for 1.25 hr. The mixture was diluted with dichloromethane and poured into saturated sodium carbonate solution (15 mL). The organic phase was separated, dried over magnesium sulfate and concentrated to give the crude title compound as a 6:1 mixture trans:cis isomers. This mixture was used without further purification.

Provenance & Evidence