4-Bromo-2-chloroaniline → 4-(4-Bromo-2-chlorophenylamino)-5,6-dichloronicotinic acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

LiHMDS (1.0 M solution in hexanes, 53.0 mL, 53.0 mmol) was added dropwise to a stirred solution of 4-bromo-2-chlorophenylamine (7.10 g, 35.0 mmol) in THF (15 mL) cooled to −78° C. After one hour, 4,5,6-trichloronicotinic acid (3.73 g, 16.5 mmol) was added dropwise as a solution in THF (12 mL). The reaction was allowed to warm to room temperature slowly while stirring overnight. The suspension was diluted with 1 M HCl and ethyl acetate, and the aqueous phase was extracted with ethyl acetate (3×). The combined organic phases were dried over Na2SO4 and concentrated to a tan solid. The solid was triturated with diethyl ether overnight and the solids were isolated by filtration to provide the desired product (25) as a tan-colored solid (4.85 g, 75%). MS APCI (−) m/z 395, 397 (M-, Cl, Br pattern) detected.

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