Triethylamine → Ethyl 6-[4-[(2,4-dichlorobenzoyl)amino]benzoyl]-5,6-dihydropyrazolo[4,3-d][1]benzazepine-2(4H)-acetate

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Reaction Steps

To a stirred solution of 0.940 g of ethyl 6-(4-aminobenzoyl)-5,6-dihydropyrazolo[4,3-d][1]benzazepine-2(4H)-acetate in 25 ml of methylene chloride is added 369 μl of triethylamine followed by the dropwise addition of 373 μl of 2,4-dichlorobenzoyl chloride in 3.5 ml of methylene chloride. The reaction mixture is stirred at room temperature for 18 hours, washed with water, saturated NaHCO3, brine and the organic layer treated with activated carbon, and filtered through is MgSO4. The filtrate is concentrated in vacuo to a residue which is purified by flash chromatography on silica gel using 25% ethyl acetate in methylene chloride to give 380 mg of the desired product as white crystals, m.p. 164°-167° C. The mother liquors are combined, evaporated in vacuo to a residue which is dissolved in 25% ethyl acetate in chloroform to give 535 mg of off-white solid, m.p. 160°-163.5° C.

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