反応 #46135

反応方程式

2-Phenyl-3,4-dihydro-2H-1,4-benzothiazine

bromo-phenyl-acetic acid methyl ester

2-amino-benzenethiol

→

2-phenyl-4H-1,4-benzothiazin-3-one

溶媒

EtOAc

water

DMF

反応条件

後処理

1. 1
   ろ過the crude product was collected by filtration
2. 2
   洗浄washed with warm EtOAc
3. 3
   その他dried

実験手順

2-Phenyl-3,4-dihydro-2H-1,4-benzothiazine: To bromo-phenyl-acetic acid methyl ester (4.88 g, 21 mmol) in DMF (15 mL) under an argon atmosphere was added 2-amino-benzenethiol (2.3 mL, 21 mmol) and the reaction was stirred at rt overnight. The reaction mixture was diluted with EtOAc (5 mL) and water (50 mL) and the crude product was collected by filtration, washed with warm EtOAc, and dried to give 2-phenyl-4H-1,4-benzothiazin-3-one as a white solid (3.49 g). LC/MS m/z 242 (M+H)+. To this intermediate (3.48 g, 14.4 mmol) in THF (50 mL) under an argon atmosphere was added 1M BH3.THF (50 mL, 50 mmol) and the reaction was stirred at rt overnight. The reaction was quenched with 1N HCl and extracted with ether. The combined organic fractions were dried over MgSO4 and concentrated. 201A was purified by recrystallization from hot EtOAc/hexanes to yield pale pink crystals (1.5 g). LC/MS m/z 228.2 (M+H)+.

出典