Practical, mild and efficient electrophilic bromination of phenols by a new I(iii)-based reagent: the PIDA-AlBr3 systemElectronic supplementary information (ESI) available. See DOI: 10.1039/c8ra02982b

• Main Authors: Satkar, Yuvraj, Ramadoss, Velayudham, Nahide, Pradip D, García-Medina, Ernesto, Juárez-Ornelas, Kevin A, Alonso-Castro, Angel J, Chávez-Rivera, Ruben, Jiménez-Halla, J. Oscar C, Solorio-Alvarado, César R
• Format: Article
• Language: English
• ISSN: 2046-2069
• DOI: 10.1039/c8ra02982b

A practical electrophilic bromination procedure for phenols and phenol-ethers was developed under efficient and very mild reaction conditions. A broad scope of arenes was investigated, including the benzimidazole and carbazole core as well as analgesics such as naproxen and paracetamol. The new I( iii )-based brominating reagent PhIOAcBr is operationally easy to prepare by mixing PIDA and AlBr 3 . Our DFT calculations suggest that this is likely the brominating active species, which is prepared in situ or isolated after centrifugation. Its stability at 4 °C after preparation was confirmed over a period of one month and no significant loss of its reactivity was observed. Additionally, the gram-scale bromination of 2-naphthol proceeds with excellent yields. Even for sterically hindered substrates, a moderately good reactivity is observed. A practical electrophilic bromination procedure for the phenolic core was developed under efficient and very mild reaction conditions. The new I(iii)-based brominating reagent PhIOAcBr operationally easy to prepare by mixing PIDA and AlBr 3 was used.