1-Butanol → 7-[(3-Chloro-2-methylphenyl)carbonyl]-3-(1,3-thiazol-2-yl)-5,6,7,8-tetrahydro[1,2,4]triazolo[4,3-a]pyrazine

Participants

Reaction Steps

4-[(3-Chloro-2-methylphenyl)carbonyl]-2-piperazinone (I134) (185 mg, 0.732 mmol) was suspended in dry Dichloromethane (DCM) (3 mL) before treating with trimethyloxonium tetrafluoroborate (137 mg, 0.879 mmol) and stirring for 16 hours at RT, under argon before adding 1,3-thiazole-2-carbohydrazide (I51) (157 mg, 1.098 mmol) and stirring for a further 4 hours. 1-Butanol (3.00 mL) was added then DCM was removed by evaporation and the residue was heated at 110° C. for 3 hours. The reaction was cooled to RT overnight and then worked up by diluting with DCM (50 ml), washing with saturated sodium bicarbonate solution (50 ml). The aqueous layer was extracted with DCM (2×30 ml), the combined extracts were washed with brine (30 ml), dried (MgSO4), filtered and evaporated to afford an orange gum, of crude material which was purified by MDAP. The desired fractions were isolated, combined and evaporated to afford a white solid, 125 mg. This was dried over the weekend at 40° C. and then dried overnight in a vacuum oven at 40° C. to afford the white solid of desired product in 115 mg.

Provenance & Evidence