Timaxel ,Specia, France ,1983
5-Methyl-dibenzo[b,f]azepine (4.1 g), N-diethylaminoborane (1.7 g) and freshly distilled toluene (150 cc) are introduced into a 500 cc three-neck flask equipped with a dropping funnel and a condenser, and protected against moisture by a calcium chloride guard tube. The solution is heated under reflux (110°C) for 22 hours under a nitrogen atmosphere and then cooled. A 2 N aqueous sodium hydroxide solution (33 cc) is then run in followed by an 0.316 N aqueous methylchloramine solution (190 cc), the addition of which takes 9 minutes. The mixture is stirred for 1 hour and then decanted. The organic layer is washed with water until it has a pH of 6 and is then extracted with 2 N hydrochloric acid (5 times 50 cc), dried over sodium sulfate, filtered and evaporated. Recrystallization of the residue from petroleum ether yields some unconverted 5-methyl-dibenzo[b,f]azepine (2.17 g).
The aqueous acid solution is rendered alkaline by adding 2 N sodium hydroxide solution. After extracting with diethyl ether (3 times 100 cc), drying the extracts over potassium carbonate, treating them with decolorizing charcoal, filtering and evaporating the ether, a yellowish oil (0.9 g), identified as 5-methyl-10-methylamino-10,11-dihydrodibenzo[b,f]azepine, is obtained in
a yield of 37.5%.
Methylchloramine can be prepared by adding an aqueous solution of sodium
hypochlorite to an aqueous solution of methylamine in accordance with the
process described by W.S. Metcalf, J. Chem. Soc.1942,148.