When 1-butene is subjected to the reactions in the order of 1-mCPBA, NaSH, and H2O, the final product is expected to be 1,2-butanediol.
Explanation: The first step involves the reaction of 1-butene with 1-mCPBA, which is a peracid commonly used for epoxidation. This reaction converts the double bond of 1-butene into an epoxide, specifically forming an epoxide at the first and second carbon. Next, the epoxide ring undergoes ring-opening in the presence of NaSH, where sodium hydrosulfide acts as a nucleophile. It attacks the epoxide, leading to the formation of a thiol at one position and simultaneously opening the ring. Finally, the reaction with H2O results in hydrolysis of the thiol group, resulting in the formation of 1,2-butanediol. Thus, the combination of these reactions transforms the starting material into 1,2-butanediol.