反应详情

温度

40 °C

(2,4-Dimethoxy-phenyl)-(2-methoxy-4-nitro-phenyl)-methanone (394) (0.4 g, 1.26 mmol) was dissolved in CH2Cl2 and BBr3 was added. The mixture was heated to 40° C. while shaking in a sealed 40 mL I-Chem vial for 16 h. TLC (Rf: 0.5 compared to Rf: 0.65 for compound 394 in 1:1 hexane/EtOAc, single spot) indicated the complete de-methylation at this point. Purification by flash chromatography on silica gel using a gradient of hexane and EtOAc (eluding with 15–100% EtOAc/hexane in 30 minutes) gave the desired product (395) as a yellow solid upon concentration (0.255 g, 0.927 mmol, 73.5%). The product was used in the next step without further characterization.

1. customPurification by flash chromatography on silica gel using a gradient of hexane and EtOAc (eluding with 15–100% EtOAc/hexane in 30 minutes)