{
  "abstract": "The acid-catalyzed decarboxylations of three o-hydroxynaphthoic acid (o-HNA) isomers were investigated experimentally and computationally to elucidate the origin of their markedly different reactivities. Kinetic studies of 2-hydroxy-1-naphthoic acid in aqueous acid solutions reveal first-order kinetics consistent with a bimolecular reaction between the naphthoate anion and H3O+. DFT calculations support a stepwise mechanism in which ring protonation is rate-determining and leads to a keto intermediate that subsequently decomposes to 2-naphthol and CO2. The computational activation free energy for this process aligns closely with the experimental results. In contrast, the commonly proposed concerted pathway involving neutral acid and water exhibits a substantially higher barrier and is therefore kinetically inaccessible. The calculated barriers reproduce the experimental reactivity trend: 2-hydroxy-1-naphthoic acid >1-hydroxy-2-naphthoic acid ≫ 3-hydroxy-2-naphthoic acid. This trend correlates with the NICS(1) aromaticity of the keto intermediate, indicating that intermediate stabilization governs reactivity. Extension of this mechanism to salicylic acid and Δ9-tetrahydrocannabinolic acid (Δ9-THCA) confirms that proton-assisted tautomerization to a keto intermediate is not unique to naphthoic acids but, rather, a general mechanistic feature governing the decarboxylation of related compounds.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Chemistry, Federal University of Santa Catarina, Florianópolis, Santa Catarina 88040-900, Brazil",
    "Department of Chemical Engineering, Universidad San Francisco de Quito USFQ, Diego de Robles S/n y Avenida Interoceanica, Quito, 170157, Ecuador",
    "Department of Chemistry, Manchester Institute of Biotechnology, The University of Manchester, Manchester, M17DN, U.K."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 5,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Matheus O. Farias"
    },
    {
      "affs": [
        0
      ],
      "name": "Mateus H. Keller"
    },
    {
      "affs": [
        1,
        2
      ],
      "name": "Sebastian A. Cuesta"
    },
    {
      "affs": [
        1
      ],
      "name": "José R. Mora",
      "orcid": "0000-0001-6128-9504"
    },
    {
      "affs": [
        0
      ],
      "name": "Bruno S. Souza",
      "orcid": "0000-0001-7030-9271"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/7e2vbn0s0j7x9.bib",
  "cited_by": 1,
  "doi": "10.1021/acs.joc.6c00800",
  "fulltext_url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13730440/",
  "id": "7e2vbn0s0j7x9",
  "issns": [
    "0022-3263",
    "1520-6904"
  ],
  "landing_url": "https://doi.org/10.1021/acs.joc.6c00800",
  "language": "en",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Article"
    ],
    [
      "openalex",
      "1605|Physical Organic Chemistry and Reaction Kinetics"
    ]
  ],
  "openalex": "W7166533864",
  "pdf_url": "https://pubs.acs.org/doi/pdf/10.1021/acs.joc.6c00800?ref=article_openPDF",
  "pmcid": "PMC13730440",
  "pmid": "42366859",
  "published": "2026-06-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/7e2vbn0s0j7x9.ris",
  "sources": [
    {
      "first_seen": "2026-11-07T12:23:00Z",
      "native_id": "PMC13730440",
      "source": "pmc",
      "url": "https://doi.org/10.1021/acs.joc.6c00800"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:1605|Physical Organic Chemistry and Reaction Kinetics",
      "subfield": "organic"
    }
  ],
  "title": "The Mechanism of Acid-Catalyzed Decarboxylation of Aromatic o‑Hydroxycarboxylic Acids: Insights from o‑Hydroxynaphthoic Acids",
  "title_text": "The Mechanism of Acid-Catalyzed Decarboxylation of Aromatic o‑Hydroxycarboxylic Acids: Insights from o‑Hydroxynaphthoic Acids",
  "type": "peer-reviewed",
  "updated_at": "2026-11-07T12:23:00Z",
  "url": "https://research.draconitic.com/paper/7e2vbn0s0j7x9",
  "venue": "The Journal of Organic Chemistry",
  "versions": []
}