JEE Main 12 Jan 2019 Morning Question 5
Question: $ CH _3CH _2-\underset{\begin{smallmatrix} | \\ Ph \end{smallmatrix}}{\overset{\begin{smallmatrix} OH \\ | \end{smallmatrix}}{\mathop{C}}},-CH _3 $ cannot be prepared by [JEE Main Online Paper Held On 12-Jan-2019 Morning]
Options:
A) $ PhCOCH _3+CH _3CH _2MgX $
B) $ HCHO+PhCH(CH _3)CH _2MgX $
C) $ PhCOCH _2CH _3+CH _3MgX $
D) $ CH _3CH _2COCH _3+PhMgX $
Show Answer
Answer:
Correct Answer: B
Solution:
Formaldehyde on reaction with Grignard’s reagent always forms primary alcohol.
The required product is tertiary alcohol.
Thus formaldehyde cannot be used to prepare it.
