{
  "abstract": "Hydride-free electrocatalytic semi-hydrogenation offers an alternative to metal-hydride-based platforms, yet controlling alkene stereochemistry through such pathways remains challenging. Herein, we report an E-selective, redox-mediated Co-catalyzed platform enabled by cooperative control of the catalyst coordination sphere via ligand denticity and acid identity. Using a triphosphine ligand and ammonium chloride acid reverses the stereochemical preference of a previously developed Z-selective system, providing access to a range of E-alkenes in high yields and excellent stereoselectivity (up to 92% yield and >20:1 E:Z). Experimental and computational mechanistic studies support a mechanism involving a distinct proton transfer step with a chloride-mediated organization of the ammonium proton donor and Co catalyst. This allows for an initial inner-sphere protonation prior to cobaltocene-mediated reduction of the resultant Co(III)-alkenyl intermediate, followed by subsequent outer-sphere protonation to yield trans alkenes. These findings illustrate that coordination-sphere organization and precise control of proton transfer pathways may serve as complementary design principles in stereoselective electrocatalysis.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Chemistry",
    "Boston University",
    "Department of Chemistry and Biochemistry",
    "University of California"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 5,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Bryan Parnitzke"
    },
    {
      "affs": [
        2,
        3
      ],
      "name": "Yaning Liu"
    },
    {
      "affs": [
        2,
        3
      ],
      "name": "Lupita S. Ramirez"
    },
    {
      "affs": [
        2,
        3
      ],
      "name": "Osvaldo Gutierrez"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Joseph Derosa",
      "orcid": "0000-0001-8672-4875"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/0cbbq6s6bjj2b.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15010969/v1",
  "fulltext_url": null,
  "id": "0cbbq6s6bjj2b",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010969/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",
      "1604|Asymmetric Hydrogenation and Catalysis"
    ]
  ],
  "openalex": "W7223316357",
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-23",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/0cbbq6s6bjj2b.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:26Z",
      "native_id": "10.26434/chemrxiv.15010969",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010969/v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:1604|Asymmetric Hydrogenation and Catalysis",
      "subfield": "inorganic"
    }
  ],
  "title": "Coordination Sphere Control Enables Hydride-Free Tandem Electrocatalytic E-Selective Semi-Hydrogenation",
  "title_text": "Coordination Sphere Control Enables Hydride-Free Tandem Electrocatalytic E-Selective Semi-Hydrogenation",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:26Z",
  "url": "https://research.draconitic.com/paper/0cbbq6s6bjj2b",
  "venue": "ChemRxiv",
  "versions": []
}