JEE Advanced Previous Year Questions of Chemistry with Solutions are available at eSaral. Practicing JEE Advanced Previous Year Papers Questions of Chemistry will help the JEE aspirants in realizing the question pattern as well as help in analyzing weak & strong areas.
Simulator
Previous Years JEE Advance Questions
Paragraph for Question Nos. 1 to 3
A carbonyl compound P, which gives positive iodoform test, undergoes reaction with MeMgBr followed by dehydration to give an olefin Q. Ozonolysis of Q leads to a dicarbonyl compound R, which undergoes intramolecular aldol reaction to give predominantly S.
[IIT 2009]
[IIT 2009]
[IIT 2009]
Paragraph for Questions Nos. 4 to 5
An acyclic hydrocarbon P, having molecular formula $\mathrm{C}_{6} \mathrm{H}_{10}$, gave acetone as the only organic product through the following sequence of reactions, in the which Q is an intermediate organic compound.
[IIT 2011]
[IIT 2011]
[IIT 2012]
[IIT 2013]
(A) Reaction I : P and Reaction II : P (B) Reaction I : U, acetone and Reaction II : Q acetone (C) Reaction I : T, U, acetone and Reaction II : P (D) Reaction I : R, acetone and Reaction II : S acetone [IIT 2013]
In basic medium halogenation dose not stop with replacement of just one hydrogen and poly halogenation takes place because -haloketones are more reactive towards base and haloform reaction takes place In above reaction $\mathrm{Br}_{2}$ is limiting agents.
[IIT 2014]
(i) Grignard prefer to give nucleophilic addition on polar $\pi$-bond and form anion intermediate. (ii) In next step anion give intramolecular nucleophilic substitution reaction & form 5 membered ring.
[IIT 2015]
Mechanism :
[IIT 2015]
[JEE Adv. 2018]
(Atomic weight in g mol–1: H = 1, C = 12, N = 14, O = 16, Br = 80. The yield (%) corresponding to the product in each step is given in the parenthesis) [JEE Adv. 2018]
