question_answer

A Wittig reaction with an aldehyde gives

A)  ketone compound -

B)  a long chain fatty acid

C)  olefin compound

D)  epoxide

Correct Answer: C

Solution :

 This is also a mean of preparing alkene where the position of the double bond is definite. In Wittig reaction, aldehyde \[(-CHO)\] and ketone  react with methylene triphenyl phosphine \[[{{({{C}_{6}}{{H}_{5}})}_{3}}P=C{{H}_{2}}]\] to give alkene. \[C{{H}_{3}}CHO+{{({{C}_{6}}{{H}_{5}})}_{3}}P=C{{H}_{2}}\xrightarrow{{}}\]              \[\underset{\Pr opene}{\mathop{C{{H}_{3}}-CH}}\,=\underset{\begin{smallmatrix}  triphenyl\,\,phosphine \\  oxide \end{smallmatrix}}{\mathop{C{{H}_{2}}+{{({{C}_{6}}{{H}_{5}})}_{3}}P=O}}\,\]