1
|
Pal S. Cp* non-innocence and the implications of (η 4-Cp*H)Rh intermediates in the hydrogenation of CO 2, NAD +, amino-borane, and the Cp* framework - a computational study. Dalton Trans 2023; 52:1182-1187. [PMID: 36648493 DOI: 10.1039/d2dt03611h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In hydrogenation mediated by half-sandwich complexes of Rh, Cp*Rh(III)-H intermediates are critical hydride-delivery agents. For bipyridine-supported complexes, a unique transformation named 'Cp* non-innocence' leads to the appearance of (Cp*H)Rh(I) intermediates, which are purported to exhibit enhanced hydride-delivery capabilities. In this work, DFT calculations performed to compare the role of these complexes in hydrogenation reveal that (Cp*H)Rh(I) intermediates do not compete with the conventional pathway (involving Cp*Rh(III)-H); instead they can lead to sequential hydrogenation of the Cp* framework, and potentially, catalyst degradation. Thus, caution is warranted when invoking the truly homogeneous nature of hydrogenation catalysis mediated by this popular class of complexes.
Collapse
Affiliation(s)
- Shrinwantu Pal
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology, 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
| |
Collapse
|
2
|
Johnee Britto N, Jaccob M. Mechanism of formic acid dehydrogenation catalysed by Cp*Co(III) and Cp*Rh(III) complexes with N,N’-bidentate imidazoline-based ligands: A DFT exploration. MOLECULAR CATALYSIS 2023. [DOI: 10.1016/j.mcat.2022.112860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
3
|
Johnee Britto N, Jaccob M. DFT Probe into the Mechanism of Formic Acid Dehydrogenation Catalyzed by Cp*Co, Cp*Rh, and Cp*Ir Catalysts with 4,4'-Amino-/Alkylamino-Functionalized 2,2'-Bipyridine Ligands. J Phys Chem A 2021; 125:9478-9488. [PMID: 34702035 DOI: 10.1021/acs.jpca.1c05542] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The mechanistic landscape of H2 generation from formic acid catalyzed by Cp*M(III) complexes (M = Co or Rh or Ir) with diamino-/dialkylamino-substituted 2,2'-bipyridine ligand architectures have been unveiled computationally. The calculations indicate that the β-hydride elimination process is the rate-determining step for all the investigated catalysts. The dialkylamino moieties on the 2,2'-bipyridine ligand were found to reduce the activation free energy required for the rate-limiting β-hydride elimination step and increase the hydridic nature of the Ir-hydride bond, which accounts for the experimentally observed enhanced catalytic activity. Furthermore, the protonation by H3O+ ion was found to be the kinetically most favorable route than the conventional protonation by formic acid. The origin for this preference lies in the increased electrophilicity of the proton from hydronium ion which facilitates easy protonation of the metal-hydride with low activation energy barrier. The Co and Rh analogues of the chosen iridium catalyst were computationally designed and were estimated to possess a rate-determining activation barrier of 16.9 and 14.5 kcal/mol, respectively. This illustrates that these catalysts are potential candidates for FAD. The insights derived in this work might serve as a vital knowledge that could be capitalized upon for designing cost-effective catalyst for FAD in future.
Collapse
Affiliation(s)
- Neethinathan Johnee Britto
- Department of Chemistry & Computational Chemistry Laboratory, Loyola Institute of Frontier Energy (LIFE), Loyola College, University of Madras, Chennai-600 034, Tamil Nadu, India
| | - Madhavan Jaccob
- Department of Chemistry & Computational Chemistry Laboratory, Loyola Institute of Frontier Energy (LIFE), Loyola College, University of Madras, Chennai-600 034, Tamil Nadu, India
| |
Collapse
|
4
|
Johnee Britto N, Jaccob M. Deciphering the Mechanistic Details of Manganese-Catalyzed Formic Acid Dehydrogenation: Insights from DFT Calculations. Inorg Chem 2021; 60:11038-11047. [PMID: 34240859 DOI: 10.1021/acs.inorgchem.1c00757] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A comprehensive density functional theory investigation has been carried out to unravel the complete mechanistic landscape of aqueous-phase formic acid dehydrogenation (FAD) catalyzed by a pyridyl-imidazoline-based Mn(I) catalyst [Mn(PY-NHIM)(CO)3Br], which was recently reported by Beller and co-workers. The computed free energy profiles show that for the production of a Mn-formate intermediate [Mn(HCO2-)], a stepwise mechanism is both kinetically and thermodynamically favorable compared to the concerted mechanism. This stepwise mechanism involves the dissociation of a Br- ion from a Mn-bromide complex [Mn(Br)] to create a vacant site and coordination of water solvent to this vacant site, followed by the dissociative exchange of the aqua ligand with the formate ion to form Mn(HCO2-). Non-covalent interaction analysis revealed that the steric hindrance at the transition state is the cardinal reason for the preference to a stepwise mechanism. The β-hydride elimination process was estimated to be the rate-determining step with a barrier of 19.0 kcal/mol. This confirms the experimental observation. The generation of a dihydrogen-bound complex was found to occur through the protonation of Mn-hydride by a hydronium ion instead of formic acid. The mechanistic details and insights presented in this work would promote future catalytic designing and exploration of earth-abundant Mn-based catalytic systems for potential applications toward FAD.
Collapse
Affiliation(s)
- Neethinathan Johnee Britto
- Department of Chemistry & Computational Chemistry Laboratory, Loyola Institute of Frontier Energy (LIFE), Loyola College, University of Madras, Chennai 600 034, Tamil Nadu, India
| | - Madhavan Jaccob
- Department of Chemistry & Computational Chemistry Laboratory, Loyola Institute of Frontier Energy (LIFE), Loyola College, University of Madras, Chennai 600 034, Tamil Nadu, India
| |
Collapse
|
5
|
Guo J, Yin CK, Zhong DL, Wang YL, Qi T, Liu GH, Shen LT, Zhou QS, Peng ZH, Yao H, Li XB. Formic Acid as a Potential On-Board Hydrogen Storage Method: Development of Homogeneous Noble Metal Catalysts for Dehydrogenation Reactions. CHEMSUSCHEM 2021; 14:2655-2681. [PMID: 33963668 DOI: 10.1002/cssc.202100602] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 04/29/2021] [Indexed: 06/12/2023]
Abstract
Hydrogen can be used as an energy carrier for renewable energy to overcome the deficiency of its intrinsically intermittent supply. One of the most promising application of hydrogen energy is on-board hydrogen fuel cells. However, the lack of a safe, efficient, convenient, and low-cost storage and transportation method for hydrogen limits their application. The feasibility of mainstream hydrogen storage techniques for application in vehicles is briefly discussed in this Review. Formic acid (FA), which can reversibly be converted into hydrogen and carbon dioxide through catalysis, has significant potential for practical application. Historic developments and recent examples of homogeneous noble metal catalysts for FA dehydrogenation are covered, and the catalysts are classified based on their ligand types. The Review primarily focuses on the structure-function relationship between the ligands and their reactivity and aims to provide suggestions for designing new and efficient catalysts for H2 generation from FA.
Collapse
Affiliation(s)
- Jian Guo
- School of Metallurgy and Environment, Central South University, 932 Lushan Road, Changsha city, Hunan Province, 410083, P. R. China
| | - Chengkai K Yin
- Hangzhou Katal Catalyst & Metal Material Stock Co., Ltd., 7 Kang Qiao Road, Gong Shu District, Hang Zhou, Zhejiang Province, 310015, P. R. China
| | - Dulin L Zhong
- School of Metallurgy and Environment, Central South University, 932 Lushan Road, Changsha city, Hunan Province, 410083, P. R. China
| | - Yilin L Wang
- School of Metallurgy and Environment, Central South University, 932 Lushan Road, Changsha city, Hunan Province, 410083, P. R. China
| | - Tiangui Qi
- School of Metallurgy and Environment, Central South University, 932 Lushan Road, Changsha city, Hunan Province, 410083, P. R. China
| | - Guihua H Liu
- School of Metallurgy and Environment, Central South University, 932 Lushan Road, Changsha city, Hunan Province, 410083, P. R. China
| | - Leiting T Shen
- School of Metallurgy and Environment, Central South University, 932 Lushan Road, Changsha city, Hunan Province, 410083, P. R. China
| | - Qiusheng S Zhou
- School of Metallurgy and Environment, Central South University, 932 Lushan Road, Changsha city, Hunan Province, 410083, P. R. China
| | - Zhihong H Peng
- School of Metallurgy and Environment, Central South University, 932 Lushan Road, Changsha city, Hunan Province, 410083, P. R. China
| | - Hong Yao
- Hangzhou Katal Catalyst & Metal Material Stock Co., Ltd., 7 Kang Qiao Road, Gong Shu District, Hang Zhou, Zhejiang Province, 310015, P. R. China
| | - Xiaobin B Li
- School of Metallurgy and Environment, Central South University, 932 Lushan Road, Changsha city, Hunan Province, 410083, P. R. China
| |
Collapse
|
6
|
Wang WH, Wang H, Yang Y, Lai X, Li Y, Wang J, Himeda Y, Bao M. Synergistic Effect of Pendant N Moieties for Proton Shuttling in the Dehydrogenation of Formic Acid Catalyzed by Biomimetic Ir III Complexes. CHEMSUSCHEM 2020; 13:5015-5022. [PMID: 32662920 DOI: 10.1002/cssc.202001190] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 06/12/2020] [Indexed: 06/11/2023]
Abstract
Formic acid (FA) is among the most promising hydrogen storage materials. The development of efficient catalysts for the dehydrogenation of FA via molecular-level control and precise tuning remains challenging. A series of biomimetic Ir complexes was developed for the efficient dehydrogenation of FA in an aqueous solution without base addition. A high turnover frequency of 46510 h-1 was achieved at 90 °C in 1 m FA solution with complex 1 bearing pendant pyridine. Experimental and mechanistic studies revealed that the integrated pendant pyridine and pyrazole moieties of complex 1 could act as proton relay and facilitate proton shuttling in the outer coordination sphere. This study provides a new strategy to control proton transfer accurately and a new principle for the design of efficient catalysts for FA dehydrogenation.
Collapse
Affiliation(s)
- Wan-Hui Wang
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, 116023, P. R. China
- School of Chemical Engineering, Dalian University of Technology, Panjin, 124221, P. R. China
| | - Hong Wang
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, 116023, P. R. China
- School of Chemical Engineering, Dalian University of Technology, Panjin, 124221, P. R. China
| | - Yajing Yang
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, 116023, P. R. China
- School of Chemical Engineering, Dalian University of Technology, Panjin, 124221, P. R. China
| | - Xiaoling Lai
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, 116023, P. R. China
- School of Chemical Engineering, Dalian University of Technology, Panjin, 124221, P. R. China
| | - Yang Li
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, 116023, P. R. China
- School of Chemical Engineering, Dalian University of Technology, Panjin, 124221, P. R. China
| | - Jiasheng Wang
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, 116023, P. R. China
- School of Chemical Engineering, Dalian University of Technology, Panjin, 124221, P. R. China
| | - Yuichiro Himeda
- National Institute of Advanced Industrial Science and Technology, Tsukuba, 305-8569, Japan
| | - Ming Bao
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, 116023, P. R. China
- School of Chemical Engineering, Dalian University of Technology, Panjin, 124221, P. R. China
| |
Collapse
|
7
|
Iguchi M, Onishi N, Himeda Y, Kawanami H. Ligand Effect on the Stability of Water‐Soluble Iridium Catalysts for High‐Pressure Hydrogen Gas Production by Dehydrogenation of Formic Acid. Chemphyschem 2019; 20:1296-1300. [DOI: 10.1002/cphc.201900137] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Revised: 03/13/2019] [Indexed: 11/09/2022]
Affiliation(s)
- Masayuki Iguchi
- Research Institute for Chemical Process Technology Department of Materials and Chemistry National Institute of Advanced Industrial Science and Technology Sendai, Miyagi 983-8551 Japan
| | - Naoya Onishi
- Research Institute of Energy Frontier Department of Energy and Environment National Institute of Advanced Industrial Science and Technology Tsukuba, Ibaraki 305–8565
| | - Yuichiro Himeda
- Research Institute of Energy Frontier Department of Energy and Environment National Institute of Advanced Industrial Science and Technology Tsukuba, Ibaraki 305–8565
| | - Hajime Kawanami
- Research Institute for Chemical Process Technology Department of Materials and Chemistry National Institute of Advanced Industrial Science and Technology Sendai, Miyagi 983-8551 Japan
| |
Collapse
|