methyl 4-(7-methoxy-2-methyl-4-oxo-4H-thiochromen-3-yl)benzoate 、
三溴化硼 、
盐酸 在
crude product 、
4-(7-hydroxy-2-methyl-4-oxo-4H-thiochromen-3-yl)benzoic acid 作用下,
以
二氯甲烷 为溶剂,
反应 20.0h,
以to afford the desired product in Example 8 as a yellow solid (57.3 mg, 31%)的产率得到4-(7-hydroxy-2-methyl-4-oxo-4H-thiochromen-3-yl)benzoic acid