This reaction is known as HVZ reaction.
Treatment with bromine and a catalytic amount of phosphorus leads to the selective α−bromination of carboxylic acids.
JEE Main 2015 — Chemistry Organic Chemistry
In the presence of a small amount of phosphorous, aliphatic carboxylic acid reacts with chlorine or bromine to yield a reaction in which, α−hydrogen is been replaced by halogen. This reaction is known as
Held on 10 Apr 2015 · Verified 6 Jul 2026.
Etard reaction
Wolff-Kischner reaction
Rosenmund reaction
Hell-volhard-zelinsky reaction
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Sucrose hydrolyses in acidic medium into glucose and fructose by first order rate law with $t_{1/2} = 3$ hour. The percentage of sucrose remaining after $6$ hours is _______. (Nearest integer) (Given: $\log 2 = 0.3010$ and $\log 3 = 0.4771$)
Given below are two statements: Statement I: $\left(\mathrm{CH}_{3}\right)_{3} \stackrel{\oplus}{\mathrm{C}}$ is more stable than $\stackrel{\oplus}{\mathrm{C}} \mathrm{H}_{3}$ as nine hyperconjugation interactions are possible in $\left(\mathrm{CH}_{3}\right)_{3} \stackrel{\oplus}{\mathrm{C}}$. Statement II: $\stackrel{\oplus}{\mathrm{C}} \mathrm{H}_{3}$ is less stable than $\left(\mathrm{CH}_{3}\right)_{3} \stackrel{\oplus}{\mathrm{C}}$ as only three hyperconjugation interactions are possible in $\stackrel{\oplus}{\mathrm{C}} \mathrm{H}_{3}$. In the light of the above statements, choose the correct answer from the options given below
Given below are two statements: Statement I: Benzene is nitrated to give nitrobenzene, which on further treatment with $\mathrm{CH}_{3} \mathrm{COCl} / \mathrm{AlCl}_{3}$ will give  Statement II: $-\mathrm{NO}_{2}$ group is a $m$-directing, and deactivating group. In the light of the above statements, choose the most appropriate answer from the options given below
Arrange the following alkenes in decreasing order of stability.  Choose the correct answer from the options given below:
A hydroxy compound $(\mathrm{X})$ with molar mass $122 \mathrm{~g} \mathrm{~mol}^{-1}$ is acetylated with acetic anhydride, using a large excess of the reagent ensuring complete acetylation of all hydroxyl groups. The product obtained has a molar mass of $290 \mathrm{~g} \mathrm{~mol}^{-1}$. The number of hydroxyl groups present in compound (X) is:
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