{
  "abstract": "Photoexcited benzene yields multiple isomers, whereas its BN isostere 1,2-azaborine selectively forms BN-Dewar benzene (BN-DB), despite both decaying through ringpuckered S1/S0 conical intersections (CIs). This selectivity is puzzling given that BNinduced asymmetry in 1,2-azaborine creates six distinct puckering sites and potentially multiple CIs, yet only a single photoproduct is observed. Here, we map the S1/S0 CI landscape of 1,2-azaborine using CASSCF and XMS-CASPT2 and identify eight N-, B-, and C-puckered CIs that open channels to various isomers including BN-DB and BN-benzvalene (BN-BV). BN incorporation therefore does not remove the excitedstate pathways of benzene but multiplies them. Of these CIs, only the N-puckered CIs leading to BN-DB lie below the S1 minimum, a preference we trace to S1 N→B charge redistribution. We then examine whether structural modifications that alter this redistribution can change CI accessibility, considering CH3 and F substitution and changes in B and N positions. Notably, 1,4-azaborine exhibits a qualitative shift from N→B to C→B charge redistribution. Consistently, C-and B-puckered CIs lie below the S1 minimum and may provide access to BN-BV, a versatile synthetic intermediate currently obtained through two photochemical steps. Together, these results suggest that S1 charge redistribution may be a key lever for steering azaborine photochemistry and for designing more direct routes to BN-BV.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 2,
  "authors": [
    {
      "name": "Annu Yadav"
    },
    {
      "name": "Mahesh Gudem",
      "orcid": "0000-0001-7475-5463"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/24w0c7hdcr49c.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15010747/v1",
  "fulltext_url": null,
  "id": "24w0c7hdcr49c",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010747/v1",
  "language": null,
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "1606|Chemical Reactions and Mechanisms"
    ]
  ],
  "openalex": "W7223143226",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv.15010747/v1",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-21",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/24w0c7hdcr49c.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:24Z",
      "native_id": "10.26434/chemrxiv.15010747",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010747/v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:1606|Chemical Reactions and Mechanisms",
      "subfield": "physical"
    }
  ],
  "title": "Picking a Pucker: Excited-State Charge Redistribution Navigates the BN-Reshaped Conical-Intersection Landscape in Azaborine Photochemistry",
  "title_text": "Picking a Pucker: Excited-State Charge Redistribution Navigates the BN-Reshaped Conical-Intersection Landscape in Azaborine Photochemistry",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:24Z",
  "url": "https://research.draconitic.com/paper/24w0c7hdcr49c",
  "venue": "ChemRxiv",
  "versions": []
}