{
  "abstract": "We report here the synthesis and comprehensive characterization of a molecular nickel complex featuring a σ–[Ca–H–Ni] interaction. Although numerous σ–[E–H–M] species have been characterized, analogous complexes featuring heavier alkaline–earth hydrides remain exceptionally rare owing to their highly ionic and reactive nature. Reaction of [Ni(t,t,t–cdt)] (t,t,t–cdt = t,t,t–cyclododeca–1,5,9–triene) with the calcium hydride, [{(DippBDI)Ca(THF)}(μ–H)]2 affords [{(DippBDI)Ca(THF)(μ–H){Ni(t,t,t–cdt)}], representing the first well–defined Ca–H–M complex (where M = transition metal) characterized in both the solution– and solid–state. Multinuclear NMR spectroscopy, single–crystal X–ray diffraction, and computational studies collectively establish the presence and electronic structure of a σ–[Ca–H–Ni] unit, revealing a polarized interaction in which the hydride is primarily associated with nickel, while retaining a significant interaction with calcium. The isolation of this σ–[Ca–H–Ni] adduct provides a molecular framework for understanding cooperative reactivity between calcium hydrides and nickel. We show that this and related σ–[Ca–H–Ni] species are likely intermediates in the nickel–promoted hydrometallation of non–activated dienes.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Chemistry, Western University, 1151 Richmond Street, London, Canada, N8K 3G6",
    "Department of Chemistry and Biochemistry, Wilfrid Laurier University, 75 University Ave. W., Waterloo, Canada, N2L 3C5",
    "Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, 82 Wood Lane, London, United Kingdom, W12 0BZ"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 6,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Sandra Salic"
    },
    {
      "affs": [
        0
      ],
      "name": "A. Dina Dilinaer"
    },
    {
      "affs": [
        0
      ],
      "name": "Gabriel J. Jobin"
    },
    {
      "affs": [
        1
      ],
      "name": "Louise N. Dawe"
    },
    {
      "affs": [
        2
      ],
      "name": "Mark R. Crimmin"
    },
    {
      "affs": [
        0
      ],
      "name": "Marcus W. Drover",
      "orcid": "0000-0002-2186-1040"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/b4316be0z30pp.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15010815/v1",
  "fulltext_url": null,
  "id": "b4316be0z30pp",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010815/v1",
  "language": null,
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "1605|Organometallic Complex Synthesis and Catalysis"
    ]
  ],
  "openalex": "W7223186881",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv.15010815/v1",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-21",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/b4316be0z30pp.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:24Z",
      "native_id": "10.26434/chemrxiv.15010815",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010815/v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:1605|Organometallic Complex Synthesis and Catalysis",
      "subfield": "organic"
    }
  ],
  "title": "A Nickel–Capped Calcium Hydride: Implications for Diene Hydrometallation",
  "title_text": "A Nickel–Capped Calcium Hydride: Implications for Diene Hydrometallation",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:24Z",
  "url": "https://research.draconitic.com/paper/b4316be0z30pp",
  "venue": "ChemRxiv",
  "versions": []
}