question_answer

Identify the product in the reaction\[PhC\equiv CMe\xrightarrow{{{H}_{3}}{{O}^{+}},H{{g}^{2+}}}\]

A) \[PhCOC{{H}_{2}}C{{H}_{3}}\] 

B) \[PhC{{H}_{2}}C{{H}_{2}}CHO\]

C) \[PhCOCOMe\]                      

D) \[PhC{{H}_{2}}COC{{H}_{3}}\] 

Correct Answer: A

Solution :

Due to higher stability of this cation \[[Ph-\overset{\oplus }{\mathop{C}}\,=CMe]\]than methyl cation, the\[-O{{H}^{o-}}\] will attack on the benzylic cation. \[\therefore \]\[PhCOC{{H}_{2}}C{{H}_{3}}\] would be the major product. Hence, the correct option is [a].