CH3-Br + Nu- arrow CH3 - Nu + Br- The decreasing order of the rate of the above reaction with nucleophiles (Nu-) A to D is [Nu- = (A) PhO- , (B) AcO- , (C) HO-, (D) CH3O- ]

Question

CH3-Br + Nu- arrow CH3 - Nu + Br- The decreasing order of the rate of the above reaction with nucleophiles (Nu-) A to D is [Nu- = (A) PhO- , (B) AcO- , (C) HO-, (D) CH3O- ] (A) D > C > A > B (B) D > C >B > A (C) A > B > C > D (D) B > D > C > A

Tardigrade Admin · Accepted Answer

PhO- is less resonance stabilized than AcO- ion and hence is a stronger nucleophile than AcO-. Therefore, the overall nucleophilicity decreases in the order: CH3O- (D) > HO- (C) > PhO- (A) > AcO- (B) Therefore, option (a) is correct.

Q. $C H_{3} - B r + N u^{-} \to C H_{3} - N u + B r^{-}$ The decreasing order of the rate of the above reaction with nucleophiles ( $N u^{-}$ ) A to D is $[N u^{-} = (A) P h O^{-}, (B) A c O^{-}, (C) H O^{-}, (D) C H_{3} O^{-}]$

D > C > A > B

D > C >B > A

A > B > C > D

B > D > C > A

$P h O^{-}$ is less resonance stabilized than $A c O^{-}$ ion and hence is a stronger nucleophile than $A c O^{-}$ . Therefore, the overall nucleophilicity decreases in the order:
$C H_{3} O^{-} (D) > H O^{-} (C) > P h O^{-} (A) > A c O^{-} (B)$ Therefore, option (a) is correct.

Q. CH3​−Br+Nu−→CH3​−Nu+Br− The decreasing order of the rate of the above reaction with nucleophiles (Nu−) A to D is [Nu−=(A)PhO−,(B)AcO−,(C)HO−,(D)CH3​O−]