4-Pyridinecarboxylic acid, 1-oxide → 4-(5,6-dihydro-11H-imidazo[2,1-b][3]benzazepin-11-ylidene)-1-(4-pyridinylcarbonyl)-piperidine N1-oxide

Participants

Reaction Conditions

Reaction Steps

1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.61 g) was added to a solution of 6,11-dihydro-11-(4-piperidylidene)-5H-imidazo[2,1-b][3]benzazepine (C, 0.52 g), pyridine-4-carboxylic acid N-oxide (0.44 g) and 1-hydroxybenzotriazole hydrate (0.43 g)in dichloromethane (20 ml) at 0°-5° C. The reaction mixture was then allowed to stir and to warm to 25° C. overnight. Water and 1 M sodium bicarbonate solution were added, and the aqueous layer was extracted with dichloromethane. Combined organic extracts were washed sequentially with water and brine, and were dried, filtered, and concentrated to give 4-(5,6-dihydro-11H-imidazo[2,1-b][3]benzazepin-11-ylidene)-1-(4-pyridinylcarbonyl)-piperidine N1 -oxide (B, 0.54 g), m.p. 155°-159° C. from carbon tetrachloride-dichloromethane. ##STR26##

Provenance & Evidence