{
  "abstract": "Rigid, three-dimensional cyclic scaffolds are highly valued in medicinal chemistry, yet selectively accessing dis tinct cyclic frameworks from a common class of simple acyclic precursors remains a significant challenge. Herein, we report a precious-metal-free photochemical cyclization of aza-1,5-dienes that enables the substituent-controlled, divergent synthe sis of three distinct cyclic frameworks: bridged bicyclo[2.1.1]hexanes, fused bicyclo[2.2.0]hexanes, and six-membered lac tams. N-Aryl-substituted substrates preferentially undergo 5-exo-trig cyclization to afford bridged bicyclo[2.1.1]hexanes, whereas substrates bearing electron-withdrawing N-substituents such as acetyl or tosyl groups favor the 6-endo-trig pathway to furnish fused bicyclo[2.2.0]hexanes. Notably, this strategy was further extended to the synthesis of six-membered lactams from N-methyl-substituted aza-1,5-dienes under photosensitizer-free conditions. This work establishes a mild, substituent controlled strategy for skeletal divergence, enabling the selective synthesis of structurally diverse cyclic scaffolds of potential value in medicinal chemistry.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "name": "Jun-Wei Zhang"
    },
    {
      "name": "Cui-Lian Zeng"
    },
    {
      "name": "Wei-Jun Dou"
    },
    {
      "name": "Yun-He Xu",
      "orcid": "0000-0001-8817-0626"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/4kbs9vscxenbw.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15009858/v1",
  "fulltext_url": null,
  "id": "4kbs9vscxenbw",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009858/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",
      "1605|Radical Photochemical Reactions"
    ]
  ],
  "openalex": "W7220360845",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv.15009858/v1",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-05",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/4kbs9vscxenbw.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:22Z",
      "native_id": "10.26434/chemrxiv.15009858",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009858/v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:1605|Radical Photochemical Reactions",
      "subfield": "organic"
    }
  ],
  "title": "Substituent-Controlled Divergent Photocyclization of Aza-1,5 Dienes to Access Three Distinct Cyclic Frameworks",
  "title_text": "Substituent-Controlled Divergent Photocyclization of Aza-1,5 Dienes to Access Three Distinct Cyclic Frameworks",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:22Z",
  "url": "https://research.draconitic.com/paper/4kbs9vscxenbw",
  "venue": "ChemRxiv",
  "versions": []
}