Hydrochloric Acid → 2-Chlorodibenz(b,f)-1,4-oxazepin-11(10H)-one

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Reaction Conditions

Reaction Steps

The crude product (2.8 g, 9.55 mmol) was then dissolved in THF (15 ml) and 2 M LiOH (40 mmol) was added. The reaction mixture was stirred at 60° C. for 2 h and then cooled to room temperature. THF was removed by rotary evaporation and the residue was acidified with HCl (2M) to a pH of 2 and filtered. The filter cake washed with 0.1M NaOH solution and finally dried to give the crude product 2.4 g (86%). Na2S2O4 (37 mmol) was added to a solution of the crude product in 2M K2CO3 (41 mmol) and EtOH (20 ml) and the reaction was stirred for 15 min. EtOH was then removed by rotary evaporation and the resulting aqueous layer was acidified with HCl (2M) to a pH of 2 and extracted with ethyl acetate. The organic layer was washed with saturated brine, dried over anhydrous Na2SO4, filtered and evaporated by a rotary evaporator to give the crude product 1.1 g (52%). Finally, the crude product (1.1 g, 4.2 mmol), EDCI (1.20 g, 6.3 mmol), HOBt (851 mg, 6.3 mmol), DMAP (5 mg, 0.04 mmol) and TEA (18.9 mmol) were dissolved in MeCN (8 ml), and the resulting solution was heated to 140° C. in microwave for 10 min. The reaction mixture was cooled, poured into water, acidified with HCl (2M) to a pH of 2 and filtered. The filtrate was washed with 0.1 M NaOH solution and dried over anhydrous Na2SO4, filtered and evaporated by a rotary evaporator to give the product (676 mg, 66%).

Provenance & Evidence