Divergent Role of PIDA and PIFA in the AlX3 (X=Cl, Br) Halogenation of 2 Naphthol: A Mechanistic Study

Submitting author affiliation:
Guanajuato University, Guanajuato, Mexico

Beilstein Arch. 2024, 202416. https://doi.org/10.3762/bxiv.2024.16.v1

Published 20 Mar 2024

cc-by Logo
This preprint has not been peer-reviewed. When a peer-reviewed version is available, this information will be updated.


The chlorination and bromination reaction mechanisms of 2-naphthol under the previously reported PIDA- or PIFA-AlX3 (X= Cl, Br) systems by our research group, was elucidated via quantum chemical calculations within the density functional theory. The studied chlorination mechanism using PIFA and AlCl3 demonstrated better experimental and theoretical yields than when PIDA was used. Additionally, the lowest-in-energy chlorinating species involve an equilibrium between the Cl-I(Ph)-OTFA-AlCl3 and [Cl-I(Ph)+] [-OTFA-AlCl3] species more than the PhICl2 formation. On the other hand, the bromination mechanism was more efficient using PIDA and AlBr3 to form the intermediate Br-I(Ph)-OAc-AlBr3 as the brominating active species. Similarly, the PhIBr2 is higher-in-energy than our proposal. The detailed reaction mechanisms described in this work are in excellent agreement with the experimental yields. These initial results confirm that such mechanisms are energetically more likely to occur, forming the equilibrium species than in the presence of the corresponding halogenating PhIX2.

Keywords: DFT calculations, iodine(III) reagents, aromatic chlorination and bromination

Supporting Information

Format: PDF Size: 2.3 MB   Download

How to Cite

When a peer-reviewed version of this preprint is available, this information will be updated in the information box above. If no peer-reviewed version is available, please cite this preprint using the following information:

Juárez-Ornelas, K. A.; Solís-Hernández, M.; Navarro-Santos, P.; Jiménez-Halla, J. O. C.; Solorio-Alvarado, C. R. Beilstein Arch. 2024, 202416. doi:10.3762/bxiv.2024.16.v1

Download Citation

Citation data can be downloaded as file using the "Download" button or used for copy/paste from the text window below.
Citation data in RIS format can be imported by all major citation management software, including EndNote, ProCite, RefWorks, and Zotero.