question_answer

Name the reagent used to bring about the following transformation : But-2-ene to ethanal

A)  \[{{K}_{2}}C{{r}_{2}}{{O}_{7}}\] in acidic medium

B)  \[Cr{{O}_{2}}C{{l}_{2}}/{{H}_{3}}{{O}^{+}}\]

C)  PCC

D)  \[{{C}_{3}}/{{H}_{2}}O\] -Zn dust

Correct Answer: D

Solution :

                 \[\underset{but-2ene}{\mathop{C{{H}_{3}}CH=CHC{{H}_{3}}}}\,={{O}_{3}}\xrightarrow{{}}\]                                                 \[\xrightarrow{{{H}_{2}}O-Zn\,\,dust}\underset{ethanal}{\mathop{2C{{H}_{3}}CHO}}\,\]