Sodium ethoxide → 9,10-Dihydro-7H-imidazo[1′,2′:1,2]imidazo[4,5-c]-1,5-naphthyridine

Participants

Reaction Steps

Sodium ethoxide (4.2 g, 61 mmol) was added in one portion to a solution of tert-butyl 2-[2-(methylsulfonyl)-1H-imidazo[4,5-c][1,5]naphthyridin-1-yl]ethylcarbamate (20 g, 50 mmol) in ethanol (200 mL), and the resulting mixture was heated at reflux for four hours. Analysis by LC/MS indicated that no reaction had taken place, and additional sodium ethoxide (4.2 g, 61 mmol) was added. The mixture was heated at reflux overnight. Analysis by LC/MS indicated the presence of starting material, and a solution of sodium ethoxide (21% in ethanol, 150 mL) was added to the mixture. The reaction was heated at reflux for two hours and then concentrated under reduced pressure. Water was added, and the mixture was extracted with dichloromethane. A precipitate formed in the aqueous layer; the precipitate was isolated by filtration and washed with water to provide 7.3 g of 9,10-dihydro-8H-imidazo[1′,2′:1,2]imidazo[4,5-c][1,5]naphthyridine as a white solid.

Provenance & Evidence