Sodium Hydroxide → 8-Chloro-5,6-dihydro-11H-benzo[5,6]cyclohepta[1,2-b]pyridin-11-one

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Reaction Steps

Phosphorous pentachloride (95%, 97.5 g; 0.45 mol) was added to a solution of N-phenyl-3-[2-(3-chlorophenyl)ethyl]-2-pyridine carboxamide 4 (10 g; 0.30 mol) in dichloromethane (500 ml). The resulting mixture was stirred at room temperature for one hour. Aluminum chloride (158.5 g; 1.19 mol) was then added to the mixture followed by stirring at room temperature for one hour. The solution was then poured onto ice (500 g) and the resulting mixture heated to reflux for one hour before cooling to room temperature. The pH of the aqueous phase was adjusted to 14 with 10M sodium hydroxide (700 ml) and the resting suspension filtered through a sintered glass funnel. The collected solid was washed with dichloromethane (2×100 ml). The organic layer of the filtrate was separated and washed with 1M HCl (1×200+1×100 ml). The organic layer was concentrated to an oil under vacuum, toluene (100 ml) was added, and the mixture again concentrated under vacuum. The oil was dissolved in toluene (150 ml) and charcoal (3.5 g) was added. The mixture was filtered through a pad of celite followed by the addition of hexane (100 ml) to the filtrate. The mixture was cooled to 0° C. for one hour prior to filtration. The collected product was dried in a vacuum oven at 60° C. overnight. Yield 44.2 g (61%)

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