Q1 The following reaction proceeds through a

[NET Dec 2013]

(a) 1, 3-sigmatropic rearrangement

(b) 2, 3-sigmatropic rearrangement

(c) 3, 3-sigmatropic rearrangement

(d) 3, 5-sigmatropic rearrangement

Q2 The major product formed in the following reaction sequence is

[NET Dec 2013]

(a) 

(b)

(c) 

(d) 

Q3 The number of nodes present in the highest occupied molecular orbital of 1, 3, 5-hexatriene in its ground state is

[NET Dec 2013]

(a) one

(b) two

(c) three

(d) four

Q4 The conditions A-B required for the following pericyclic reactions are

[NET Dec 2013]

(a) A-Δ, B-Δ

(b) A-hv, B-Δ

(c) A- hv, B- hv

(d) A-Δ, B- hv

Q5 The number of π electrons participating and the pericyclic mode in the following reaction are

[NET Dec 2013]

(a) 4 and conrotatory

(b) 4 and disrotatory

(c) 6 and conrotatory

(d) 6 and disrotatory

Q6 In the Diels-Alder reaction, the most reactive diene amongst the following is

[NET June 2014]

(a) (4E)-1,4-hexadiene

(b) (4Z)-1,4-hexadiene

(c) (2E, 4E)-2, 4-hexadiene

(d) (2Z, 4Z)-2, 4-hexadiene

Q7 The major product formed in the following reaction is

[NET June 2014]

(a) 

 (b) 

(c) 

(d) 

Q8 The correct combination of reagents for effecting the following sequence of reaction is

[NET June 2014]

(a) A = O3/O2; B = K+-OOC-N=N-COO-+K, AcOH

(b) A = O2, Rose Bengal, hv; B = K+-OOC-N=N-COO-+K, AcOH

(c) A = O2, Rose Bengal, hv; B = H2, Pd/C

(d) A = O2, Rose Bengal, Δ; B = H2, Pd/C

Q9 The correct sequence of pericyclic reactions involved in the following transformation is

[NET Dec 2016]

(a) (i) ene reaction, (ii) [2, 3]-sigmatropic shift, (iii) [3, 3]-sigmatropic shift

(b) (i) ene reaction, (ii) [3, 3]-sigmatropic shift, (iii) [1, 3]-sigmatropic shift

(c) (i) [2, 3]-sigmatropic shift, (ii) ene reaction, (iii) [1, 3]-sigmatropic shift

(d) (i) [1, 3]-sigmatropic shift, (ii) [2, 3]-sigmatropic shift, (iii) [3, 3]-sigmatropic shift

Q10 Pericyclic reaction involved in one of the steps of the following reaction sequence is

[NET June 2014]

(a) [1, 3]-sigmatropic shift

(b) [3, 3]-sigmatropic shift

(c) [1, 5]-sigmatropic shift

(d) [2, 3]-sigmatropic shift

Q11 The major products A and B in the following reaction sequence are

[NET June 2014]

(a) 

(b) 

(c) 

(d) 

Q12 The reaction of 1-bromo-2-fluorobenzene with furan in the presence of one equivalent of Mg gives

[NET Dec 2014]

(a) 

(b) 

(c) 

(d) 

Q13 The major product of the following reaction is

[NET Dec 2014]


(a) 

(b) 

(c) 

(d) 

Q14 The products A and B in the following reaction sequence are

[NET Dec 2014]

(a) 

(b) 

(c) 

(d) 

Q15 The major product of the following reaction is

[NET Dec 2014]

(a) 

(b) 

(c) 

(d) 

Q16 The major product formed in the following reaction is

[NET June 2015]

(a) 

(b) 

(c) 

(d) 

Q17 The major products A and B formed in the following reactions are

[NET June 2015]

(a)

(b) 

(c) 

(d) 

Q18 The major product in the following sequence is

[NET June 2015]

(a) 

(b) 

(c) 

(d) 

Q19 The major product formed by photochemical reaction of (2E, 4Z, 6E)-decatriene

[NET Dec 2015]

(a) 

(b) 

(c) 

(d) 

Q20 The major product formed in the following reaction is

[NET Dec 2015]

(a) 

(b) 

(c) 

(d) 

Q21. The major product formed in the following reaction is

[NET Dec 2015]

(a)    

(b)

(c)  

(d)

Q22. The following transformation involves sequential

[NET Dec 2015]

(a) Claisen rearrangement - Cope rearrangement - ene reaction

(b) Cope rearrangement - Claisen rearrangement - ene reaction

(c) Cope rearrangement - ene reaction - Claisen rearrangement

(d) ene reaction - Claisen rearrangement - Cope rearrangement

Q23. A concerted [1,3]-sigmatropic rearrangement took place in the reaction shown below. The structure of the resulting product is

[NET Dec 2015]


(a) 

(b)

(c)  

(d)

Q24. The following transformation proceeds through two consecutive electrocyclic processes, which are

[NET June 2016]

(a) 4π con and 6π con

(b) 4π dis and 6π con

(c) 4π con and 6π dis

(d) 4π dis and 6π dis

Q25. The correct starting compound A in the following reaction is

[NET Dec 2016]

(a)

(b)

(c)

(d)

Q26. The major products A and B formed in the following reaction sequence are

[NET June 2016]

(a)

(b)

(c)

(d)

Ans Key:

Q1-c Q2-b Q3-b Q4-b Q5-d
Q6-c Q7-c Q8-b Q9-a Q10-d
Q11-a Q12-c Q13-c Q14-a Q15-d
Q16-c Q17-b Q18-d Q19-a Q20-a
Q21-c Q22-b Q23-c Q24-c Q25-b Q26-c