Cyanoacetamide → Olprinone

Participants

Reaction Steps

In 230 ml of N,N-dimethylformamide was dissolved 23.5 g of 4-dimethylamino-3-(imidazo[1,2-a]pyridin-6-yl)-3-buten-2-one. The solution was stirred at 80° to 90° C. for 12 hours, together with 9.48 g of α-cyanoacetamide and 12.2 g of sodium methoxide. After cooling, the solvnt was removed by distillation under reduced pressure and 500 ml of water was added to the residue to dissolve it. The solution was washed with 600 ml of chloroform. Next, about 5 ml of acetic acid was added to the aqueous layer to adjust pH to 6.5. Crystals precipitated upon cooling were taken by filtration. After the crystals were washed with water, acetonitrile and then ether, they were dissolved in 200 ml of a 2.5% aqueous sodium hydroxide solution. The solution was treated with activated charcoal. The filtrate was again adjusted to pH of 6.5 with about 7 ml of acetic acid. Crystals precipitated upon cooling were taken by filtration. After the crystals were washed with water, acetonitrile and then ether, they were recrystallized from 100 ml of N,N-dimethylformamide to obtain 13 g of 1,2-dihydro-6-methyl-2-oxo-5-(imidazo[1,2-a]pyridin-6-yl)-3-pyridinecarbonitrile.

Provenance & Evidence