Which of the following is the least acidic?

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

Question

(D) The acidity of phenols is determined by the stability of the phenoxide ion formed after the loss of a proton. Electron-withdrawing groups $(EWG)$

Vedclass · Accepted Answer

$o$-Cresol

Vedclass · Answer

(D) The acidity of phenols is determined by the stability of the phenoxide ion formed after the loss of a proton. Electron-withdrawing groups $(EWG)$ like $-NO_2$ and $-Cl$ stabilize the phenoxide ion through $-I$ and $-M$ effects,thereby increasing acidity. Electron-donating groups $(EDG)$ like $-CH_3$ (present in $o$-cresol) destabilize the phenoxide ion through $+I$ and hyperconjugation effects,thereby decreasing acidity. Comparing the options: $1$. $p$-Nitrophenol: Strongest acid due to the powerful $-M$ effect of $-NO_2$. $2$. $p$-Chlorophenol: Acidic due to the $-I$ effect of $-Cl$. $3$. Phenol: Baseline acidity. $4$. $o$-Cresol: Least acidic due to the electron-donating $+I$ effect of the methyl group. Therefore,$o$-cresol is the least acidic.

Similar Questions

The major product of the following reaction is:

What is the product obtained in the Reimer-Tiemann reaction?

The major product of the following reaction sequence is:
Aniline $\xrightarrow[(i) NaNO_2, HCl, 273-278K]{(ii) H_2O, warm} \text{Product}$ $\xrightarrow[(iv) NaOH]{(iii) Br_2, (excess)} \text{Product}$ $\xrightarrow{(v) CH_3I} \text{Final Product}$

The major product of the given reaction is
$3-methoxyphenol$ $\xrightarrow[{(ii) \ H_2SO_4, \ heat}]{{(i) \ OHCCH_2COCl}}$

What will be the product $(A)$ in the following reaction?
$p$-cresol $\xrightarrow[(ii) H^+]{(i) CHCl_3/KOH} (A)$

Vedclass Test Series

Exam Paper Generator

Online Exam Module