---
OA_type: closed access
_id: '22141'
abstract:
- lang: eng
  text: Molecular electrocatalysis is commonly interpreted through electronic descriptors,
    implicitly treating catalysts as mechanically passive during redox cycling. Yet,
    electron transfer often imposes structural demands on molecular scaffolds, raising
    the question of whether internal mechanical constraints can directly regulate
    access to reactive states and, in turn, catalytic outcomes. Addressing this question
    has remained challenging because mechanical effects are typically inseparable
    from changes in composition or electronic structure. Here, we achieve this separation
    by exploiting two constitutionally identical molecular catalysts whose only distinction
    is ligand geometry. This minimal geometric variation enables or suppresses intramolecular
    hydrogen bonding, thereby encoding distinct mechanical constraints that isolate
    molecular mechanics as a variable in redox accessibility. In the α isomer, molecular
    constraints impose a mechanically enforced barrier that severely limits access
    to the reactive redox state. This disrupts the temporal ordering of elementary
    steps, and diverts reactivity toward competing hydrogen evolution, eroding both
    selectivity and stability. In contrast, mechanical compliance in the β isomer
    enables facile access to the redox-active state, allowing CO2 activation to intrinsically
    outpace water activation and yielding CO selectivities exceeding 92%. Operando
    spectroscopy and real-time mass spectrometry, combined with computational simulation,
    directly resolve this mechanically gated reaction sequence as it unfolds. Molecular
    mechanics thus emerge as determinants that link electron flow to reaction sequencing
    and catalytic selectivity, revealing that constitutionally similar catalysts can
    be mechanically, and therefore catalytically, distinct.
article_number: jacs.6c02632
article_processing_charge: No
article_type: original
author:
- first_name: Rahul Mahadeo
  full_name: Mendhe, Rahul Mahadeo
  last_name: Mendhe
- first_name: Neethu
  full_name: Christudas Dargily, Neethu
  id: 19edef5c-384c-11ef-8188-c73c9c31d601
  last_name: Christudas Dargily
- first_name: Alagar Raja
  full_name: Kottaichamy, Alagar Raja
  last_name: Kottaichamy
- first_name: Shifali
  full_name: Dutt, Shifali
  last_name: Dutt
- first_name: Mukaddar
  full_name: Sk, Mukaddar
  last_name: Sk
- first_name: Harish
  full_name: Makri Nimbegondi Kotresh, Harish
  last_name: Makri Nimbegondi Kotresh
- first_name: Musthafa
  full_name: Ottakam Thotiyl, Musthafa
  last_name: Ottakam Thotiyl
citation:
  ama: Mendhe RM, Christudas Dargily N, Kottaichamy AR, et al. Mechanical gating of
    redox access in molecular electrocatalysis. <i>Journal of the American Chemical
    Society</i>. 2026. doi:<a href="https://doi.org/10.1021/jacs.6c02632">10.1021/jacs.6c02632</a>
  apa: Mendhe, R. M., Christudas Dargily, N., Kottaichamy, A. R., Dutt, S., Sk, M.,
    Makri Nimbegondi Kotresh, H., &#38; Ottakam Thotiyl, M. (2026). Mechanical gating
    of redox access in molecular electrocatalysis. <i>Journal of the American Chemical
    Society</i>. American Chemical Society. <a href="https://doi.org/10.1021/jacs.6c02632">https://doi.org/10.1021/jacs.6c02632</a>
  chicago: Mendhe, Rahul Mahadeo, Neethu Christudas Dargily, Alagar Raja Kottaichamy,
    Shifali Dutt, Mukaddar Sk, Harish Makri Nimbegondi Kotresh, and Musthafa Ottakam
    Thotiyl. “Mechanical Gating of Redox Access in Molecular Electrocatalysis.” <i>Journal
    of the American Chemical Society</i>. American Chemical Society, 2026. <a href="https://doi.org/10.1021/jacs.6c02632">https://doi.org/10.1021/jacs.6c02632</a>.
  ieee: R. M. Mendhe <i>et al.</i>, “Mechanical gating of redox access in molecular
    electrocatalysis,” <i>Journal of the American Chemical Society</i>. American Chemical
    Society, 2026.
  ista: Mendhe RM, Christudas Dargily N, Kottaichamy AR, Dutt S, Sk M, Makri Nimbegondi
    Kotresh H, Ottakam Thotiyl M. 2026. Mechanical gating of redox access in molecular
    electrocatalysis. Journal of the American Chemical Society., jacs. 6c02632.
  mla: Mendhe, Rahul Mahadeo, et al. “Mechanical Gating of Redox Access in Molecular
    Electrocatalysis.” <i>Journal of the American Chemical Society</i>, jacs. 6c02632,
    American Chemical Society, 2026, doi:<a href="https://doi.org/10.1021/jacs.6c02632">10.1021/jacs.6c02632</a>.
  short: R.M. Mendhe, N. Christudas Dargily, A.R. Kottaichamy, S. Dutt, M. Sk, H.
    Makri Nimbegondi Kotresh, M. Ottakam Thotiyl, Journal of the American Chemical
    Society (2026).
date_created: 2026-06-24T18:29:56Z
date_published: 2026-06-19T00:00:00Z
date_updated: 2026-06-29T06:39:21Z
day: '19'
doi: 10.1021/jacs.6c02632
extern: '1'
external_id:
  pmid:
  - '42319128'
language:
- iso: eng
month: '06'
oa_version: None
pmid: 1
publication: Journal of the American Chemical Society
publication_identifier:
  eissn:
  - 1520-5126
  issn:
  - 0002-7863
publication_status: epub_ahead
publisher: American Chemical Society
quality_controlled: '1'
status: public
title: Mechanical gating of redox access in molecular electrocatalysis
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2026'
...