Hydrochloric Acid → 1-(5-Bromopyridin-2-yl)-1,4-diazepane

Participants

Reaction Conditions

Reaction Steps

6 ml of a solution of hydrogen chloride (6N) in isopropanol are added to a solution of 1.63 g (4.4 mmol) of 1,1-dimethylethyl 4-(5-bromo-2-pyridyl)-1,4-diazepane-1-carboxylate, obtained in step 11.1, in 12 ml of dioxane and 4 ml of ethanol. This reaction mixture is maintained at 70° C. for 3 hours. The mixture is allowed to cool to room temperature and is then concentrated under reduced pressure. 1.32 g of a white solid are obtained after crystallization from acetone. These crystals are taken up in 10 ml of dichloromethane and the reaction medium is basified to pH=14, by adding 28% ammonia solution. The organic phase is recovered by filtration through a hydrophobic cartridge and the filtrate is concentrated under reduced pressure. 0.96 g of product is obtained in the form of an oil, and is used without further purification in the following step.

Provenance & Evidence