1) SnCl4 takes cl- from acid halide to form SnCl5+. A positive site is fomed at c with double bond O. 2)This electrophile formed attacks the position of sulphur. Because, the lone pair gets conjugated and forms Negative sites on both positions. But it attacks -Carbon with less congestion(presence of less bulky groups). 3) It combines to form given product aong with release of HCl. Solution 1) SnCl4 takes cl- from acid halide to form SnCl5+. A positive site is fomed at c with double bond O. 2)This electrophile formed attacks the position of sulphur. Because, the lone pair gets conjugated and forms Negative sites on both positions. But it attacks -Carbon with less congestion(presence of less bulky groups). 3) It combines to form given product aong with release of HCl..