Facile, Metal-free, Highly Para-Selective Room Temperature Monobromination of Aniline Analogs
Issued Date
2025-04-25
Resource Type
eISSN
23656549
Scopus ID
2-s2.0-105003711557
Journal Title
ChemistrySelect
Volume
10
Issue
16
Rights Holder(s)
SCOPUS
Bibliographic Citation
ChemistrySelect Vol.10 No.16 (2025)
Suggested Citation
Bovonsombat P., Hocks A., Kittithanaluk P., We J.T., Khanthapura P., Choosakoonkriang S., Srikamhom N., Ploymanee F. Facile, Metal-free, Highly Para-Selective Room Temperature Monobromination of Aniline Analogs. ChemistrySelect Vol.10 No.16 (2025). doi:10.1002/slct.202500544 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/110069
Title
Facile, Metal-free, Highly Para-Selective Room Temperature Monobromination of Aniline Analogs
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Abstract
A highly para-selective, room temperature, direct bromination of aniline and analogs with N-bromosuccinimide is reported herein. Benzylic bromination was not observed in substrates with competing benzylic hydrogens. Cyano, amide, ester, carboxylic acid, methoxy, N-alkyl and N,N-dialkyl groups, morpholine, and piperazine rings were tolerated. Gram-scale reaction was demonstrated with selected substrates. This para-selective bromination methodology was used in our one-pot sequential chlorination and iodination demonstrative synthesis of mixed dihalo- and trihalo-aniline analogs. The ortho-para transition states and the corresponding sigma complexes’ energy differences were determined to account for the high para-selectivity of aniline bromination. Both differences are comparable in values, but the energy difference for the sigma complexes is slightly greater than the energy difference of the transition states.