反应详情

To a stirred solution of 4-methyl-3-nitrobenzoyl chloride (Sigma-Aldrich, 2.0 g, 10 mmol) in CH2Cl2 (50 mL) is added trimethylsilyldiazomethane (2.0 M in hexanes, 40 mmol). The mixture is stirred for 2 hours at room temp, then cooled to 0° C. and a solution of HBr/HOAc (6.33 mL, 33% of HBr in HOAc, 35 mmol) is added dropwise (N2 evolution). After addition the mixture is stirred at 0° C. for 5 minutes, concentrated and purified by silica gel chromatography (CH2Cl2) to give the title compound (2.42 g, 93% yield) as a light yellow solid: Rf 0.61 (CH2Cl2)

1. temperaturecooled to 0° C.
2. additionAfter addition the mixture
3. stirringis stirred at 0° C. for 5 minutes
4. concentrationconcentrated
5. custompurified by silica gel chromatography (CH2Cl2)