JEE Main 202621 JanuaryEvening Shift
- Exam
- JEE Main
- Year
- 2026
- Date
- 21 January
- Shift
- Evening Shift
- Subject
- Chemistry
- Chapter
- Amines
JEE Main 2026 · 21 January · Evening Shift · Chemistry · Amines
Consider the above sequence of reactions. The number of bromine...
Consider the above sequence of reactions. The number of bromine atom(s) in the final product (P) will be :
Options
- A3
- B5
- C6
- D1
Correct answer
B. 5
Step-by-step solution
The reaction sequence is as follows:
1. Bromination of nitrobenzene with results in meta-bromonitrobenzene because the group is meta-directing. (1 Br atom)
2. Reduction of the nitro group using followed by pH neutralization converts to . The product is m-bromoaniline.
3. Reaction with (bromine water) on m-bromoaniline: The group is highly activating and ortho/para directing. In m-bromoaniline, the positions ortho and para to are vacant (positions 2, 4, and 6 relative to ). Bromine water causes polybromination at all available ortho and para positions. This adds 3 more bromine atoms. (Total 1 + 3 = 4 Br atoms)
4. Diazotization with at converts the group into a diazonium salt .
5. Sandmeyer reaction with replaces the diazonium group with a bromine atom. (Total 4 + 1 = 5 Br atoms)
The final product (P) is 1,2,3,4,5-pentabromobenzene. Therefore, the number of bromine atoms in the final product is 5.
1. Bromination of nitrobenzene with results in meta-bromonitrobenzene because the group is meta-directing. (1 Br atom)
2. Reduction of the nitro group using followed by pH neutralization converts to . The product is m-bromoaniline.
3. Reaction with (bromine water) on m-bromoaniline: The group is highly activating and ortho/para directing. In m-bromoaniline, the positions ortho and para to are vacant (positions 2, 4, and 6 relative to ). Bromine water causes polybromination at all available ortho and para positions. This adds 3 more bromine atoms. (Total 1 + 3 = 4 Br atoms)
4. Diazotization with at converts the group into a diazonium salt .
5. Sandmeyer reaction with replaces the diazonium group with a bromine atom. (Total 4 + 1 = 5 Br atoms)
The final product (P) is 1,2,3,4,5-pentabromobenzene. Therefore, the number of bromine atoms in the final product is 5.