For the given reaction R-C(R_1)(R_2)-X xright | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(C) Racemisation occurs via an $S_N1$ mechanism,which involves the formation of a carbocation intermediate. The stability of the carbocation determine

Vedclass · Accepted Answer

$C_6H_5-C(Br)(C_6H_4-OCH_3)(C_6H_4-CH_3)$

Vedclass · Answer

(C) Racemisation occurs via an $S_N1$ mechanism,which involves the formation of a carbocation intermediate. The stability of the carbocation determines the ease of $S_N1$ reaction and the extent of racemisation.Greater stability of the carbocation leads to a more planar and long-lived intermediate,which allows for more effective attack from both sides,resulting in higher racemisation.Comparing the substrates:Option $A$ and $B$ form secondary carbocations,which are less stable.Option $C$ forms a tertiary carbocation stabilized by two phenyl rings,one of which has an electron-donating $-OCH_3$ group at the para position,significantly increasing the stability of the carbocation via resonance.Option $D$ forms a tertiary carbocation,but it is destabilized by the electron-withdrawing $-NO_2$ and $-NH_3^+$ groups.Therefore,the substrate in option $C$ forms the most stable carbocation,leading to maximum racemisation.

For the given reaction $R-C(R_1)(R_2)-X \xrightarrow{HOH} R-C(R_1)(R_2)-OH$,which substrate will give maximum racemisation?

Similar Questions

Consider the reactions:
$(i) \ (CH_3)_2CHCH_2Br \xrightarrow{C_2H_5OH} (CH_3)_2CHCH_2OC_2H_5 + HBr$
$(ii) \ (CH_3)_2CHCH_2Br \xrightarrow{C_2H_5O^-} (CH_3)_2CHCH_2OC_2H_5 + Br^-$
The mechanisms of reaction $(i)$ and $(ii)$ are respectively:

Which among the following has the lowest boiling point?

Which of these does not form a Grignard reagent?

Which of the following compounds gives a racemic mixture on nucleophilic substitution?
$(a)$ $CH_3-CH(Br)-C_2H_5$
$(b)$ $CH_3-C(Br)(CH_3)-C_2H_5$
$(c)$ $C_2H_5-CH(C_2H_5)-CH_2Br$

The $S_{N}2$ reaction mechanism proceeds through ........

Vedclass Test Series

Exam Paper Generator

Online Exam Module