Boron tribromide → 4-(4-chlorobenzyl)-6-bromo-2-(2-hydroxyphenyl)-1,2,4-triazine-3,5(2H,4H)-dione

Participants

Reaction Conditions

Reaction Steps

According to Scheme 9 Step 1: To a solution of 4-(4-chlorobenzyl)-6-bromo-2-(2-methoxyphenyl)-1,2,4-triazine-3,5(2H,4H)-dione (150 mg, 0.35 mmol) in DCM (2 ml) cooled at −78° C. was added dropwise BBr3 (0.710 mL, 0.710 mmol). The reaction mixture was stirred 1 h at −78° C. and was quenched with MeOH. The mixture was allowed to reach room temperature. Water was added and the aqueous layer was extracted with DCM (×3). The combined organic layers were successively washed with water, brine, dried over MgSO4, filtered and concentrated. 131 mg (yield=90%) of 4-(4-chlorobenzyl)-6-bromo-2-(2-hydroxyphenyl)-1,2,4-triazine-3,5(2H,4H)-dione were recovered as a beige solid which was used in the next step without any purification.

Provenance & Evidence