Method for preparing 3-bromoacetyl-5-chloro-2-thiophenylsulfonamide

The invention belongs to the technical field of pharmaceutical chemicals and particularly relates to a method for preparing an intermediate of Brinzolamide, i.e., 3-bromoacetyl-5-chloro-2-thiophenylsulfonamide. The method comprises the following steps: subjecting 3-acetyl-5-chloro-2-thiophenyl sulfonamide, which serves as a raw material, and N-bromosuccinimide, which serves as a bromination reagent, to temperature-controlled heating until the raw material reacts completely, concentrating a solvent, and then, carrying out crystallization; and adding solids obtained through centrifugation into water, carrying out pulping, carrying out centrifugation again, and then, carrying out baking, thereby obtaining the 3-bromoacetyl-5-chloro-2-thiophenylsulfonamide. According to the method, the operation is simple and convenient, the production is environmentally friendly, and the obtained product is relatively high in yield, so that the method is more applicable to large-scale production. 本发明属于医药化工技术领域，具体涉及种制备布林佐胺中间体3-溴乙