1
|
Lu Z, Mitra D, Narayan SR, Williams TJ. An Immobilized (Carbene)Nickel Catalyst for Water Oxidation. Polyhedron 2024; 252:116880. [PMID: 38435834 PMCID: PMC10907011 DOI: 10.1016/j.poly.2024.116880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2024]
Abstract
The oxygen evolution reaction (OER) of water splitting is essential to electrochemical energy storage applications. While nickel electrodes are widely available heterogeneous OER catalysts, homogeneous nickel catalysts for OER are underexplored. Here we report two carbene-ligated nickel(II) complexes that are exceptionally robust and efficient homogeneous water oxidation catalysts. Remarkably, these novel nickel complexes can assemble a stable thin film onto a metal electrode through poly-imidazole bridges, making them supported heterogeneous electrochemical catalysts that are resilient to leaching and stripping. Unlike molecular catalysts and nanoparticle catalysts, such electrode-supported metal-complex catalysts for OER are rare and have the potential to inspire new designs. The electrochemical OER with our nickel-carbene catalysts exhibits excellent current densities with high efficiency, low Tafel slope, and useful longevity for a base metal catalyst. Our data show that imidazole carbene ligands stay bonded to the nickel(II) centers throughout the catalysis, which allows the facile oxygen evolution.
Collapse
Affiliation(s)
- Zhiyao Lu
- Donald P. and Katherine B. Loker Hydrocarbon Institute, Wrigley Institute for Environment and Sustainability, and Department of Chemistry, University of Southern California, Los Angeles, California, 90089-1661, United States
| | - Debanjan Mitra
- Donald P. and Katherine B. Loker Hydrocarbon Institute, Wrigley Institute for Environment and Sustainability, and Department of Chemistry, University of Southern California, Los Angeles, California, 90089-1661, United States
| | - Sri R. Narayan
- Donald P. and Katherine B. Loker Hydrocarbon Institute, Wrigley Institute for Environment and Sustainability, and Department of Chemistry, University of Southern California, Los Angeles, California, 90089-1661, United States
| | - Travis J. Williams
- Donald P. and Katherine B. Loker Hydrocarbon Institute, Wrigley Institute for Environment and Sustainability, and Department of Chemistry, University of Southern California, Los Angeles, California, 90089-1661, United States
| |
Collapse
|
2
|
Austen BJH, Clapson ML, Drover MW. Reactions of nickel boranyl compounds with pnictogen-carbon triple bonds. RSC Adv 2023; 13:19158-19163. [PMID: 37362339 PMCID: PMC10288830 DOI: 10.1039/d3ra02797j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 06/14/2023] [Indexed: 06/28/2023] Open
Abstract
The catalytic conversion of unsaturated small molecules such as nitriles into reduced products is of interest for the production of fine chemicals. In this vein, metal-ligand cooperativity has been leveraged to promote such reactivity, often conferring stability to bound substrate - a balancing act that may offer activation at the cost of turnover efficiency. This report describes the reactivity of a [(diphosphine)Ni] compound with pnictogen carbon triple bonds (R-C[triple bond, length as m-dash]E; E = N, P), where the diphosphine contains two pendant borane groups. For E = N, cooperative nitrile coordination is observed to afford {Ni}2 complexes displaying B-N interactions, whereas for E = P, B-P interactions are absent. This work additionally outlines a structure-activity relationship that uses nitrile dihydroboration as a model reaction to unveil the effect of SCS stabilization, employing [(diphosphine)Ni] where the diphosphine contains 0, 1, or 2 pendant Lewis acid groups.
Collapse
Affiliation(s)
- Brady J H Austen
- Department of Chemistry and Biochemistry, The University of Windsor 401 Sunset Avenue Windsor ON N9B 3P4 Canada
| | - Marissa L Clapson
- Department of Chemistry and Biochemistry, The University of Windsor 401 Sunset Avenue Windsor ON N9B 3P4 Canada
| | - Marcus W Drover
- Department of Chemistry and Biochemistry, The University of Windsor 401 Sunset Avenue Windsor ON N9B 3P4 Canada
| |
Collapse
|
3
|
Das S, Maity J, Panda TK. Metal/Non-Metal Catalyzed Activation of Organic Nitriles. CHEM REC 2022; 22:e202200192. [PMID: 36126180 DOI: 10.1002/tcr.202200192] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Indexed: 12/15/2022]
Abstract
Nitrile activation is a prominent topic in recent developments in chemistry, especially in organic, inorganic, biological chemistry, as well as in the natural synthesis of products and in the pharmaceutical industry. The activation of nitriles using both metal and non-metal precursors has attracted several researchers, who are exploring newer ways to synthesize novel compounds. Nitrile activation can be achieved by combining various catalytic double hydroelementation reactions, such as hydrosilylation, hydroboration, and hydrogenation of organonitriles using silanes, pinacolborane, and other sources of hydrogen. These methodologies have garnered considerable attention since they are effective in the reduction of organonitriles, whose end products are extensively applied in synthetic organic chemistry. In this review, we summarize the development of selective hydroborylation, hydrosilylation, dihydroborysilylation, and hydrogenation of organonitriles, as well as their reaction mechanisms and the role of metal complexes in the catalytic cycles. This review article explains various synthetic methodologies applied toward the reduction of organonitriles into corresponding amines.
Collapse
Affiliation(s)
- Suman Das
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi - 502 285, Sangareddy, Telangana, India
| | - Jyotirmoy Maity
- Department of Chemistry, St. Stephen's College, University of Delhi, Delhi, 110 007, India
| | - Tarun K Panda
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi - 502 285, Sangareddy, Telangana, India
| |
Collapse
|
4
|
Abstract
Cobalt-NHC complexes have emerged as an attractive class of 3d transition metal catalysts for a broad range of chemical processes, including cross-coupling, hydrogenation, hydrofunctionalization and cycloaddition reactions. Herein, we present a comprehensive review of catalytic methods utilizing cobalt-NHC complexes with a focus on catalyst structure, the role of the NHC ligand, properties of the catalytic system, mechanism and synthetic utility. The survey clearly suggests that the recent emergence of well-defined cobalt-NHC catalysts may have a tremendous utility in the design and application of catalytic reactions using more abundant 3d transition metals.
Collapse
Affiliation(s)
- Sourav Sekhar Bera
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| |
Collapse
|
5
|
Lévay K, Madarász J, Hegedűs L. Tuning the chemoselectivity of the Pd-catalysed hydrogenation of pyridinecarbonitriles: an efficient and simple method for preparing pyridyl- or piperidylmethylamines. Catal Sci Technol 2022. [DOI: 10.1039/d1cy02295d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Differentiation between the products can be fine-tuned by simply adjusting the amount of acidic additive.
Collapse
Affiliation(s)
- Krisztina Lévay
- Department of Organic Chemistry and Technology, Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, Műegyetem rkp. 3, H-1111 Budapest, Hungary
| | - János Madarász
- Department of Inorganic and Analytical Chemistry, Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, Műegyetem rkp. 3, H-1111 Budapest, Hungary
| | - László Hegedűs
- Department of Organic Chemistry and Technology, Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, Műegyetem rkp. 3, H-1111 Budapest, Hungary
| |
Collapse
|
6
|
Ghosh P, Jacobi von Wangelin A. Manganese‐Catalyzed Hydroborations with Broad Scope. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103550] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Pradip Ghosh
- Dept. of Chemistry University of Hamburg Martin Luther King Pl 6 20146 Hamburg Germany
| | | |
Collapse
|
7
|
Ghosh P, Jacobi von Wangelin A. Manganese-Catalyzed Hydroborations with Broad Scope. Angew Chem Int Ed Engl 2021; 60:16035-16043. [PMID: 33894033 PMCID: PMC8362021 DOI: 10.1002/anie.202103550] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/22/2021] [Indexed: 12/29/2022]
Abstract
Reductive transformations of easily available oxidized matter are at the heart of synthetic manipulation and chemical valorization. The applications of catalytic hydrofunctionalization benefit from the use of liquid reducing agents and operationally facile setups. Metal‐catalyzed hydroborations provide a highly prolific platform for reductive valorizations of stable C=X electrophiles. Here, we report an especially facile, broad‐scope reduction of various functions including carbonyls, carboxylates, pyridines, carbodiimides, and carbonates under very mild conditions with the inexpensive pre‐catalyst Mn(hmds)2. The reaction could be successfully applied to depolymerizations.
Collapse
Affiliation(s)
- Pradip Ghosh
- Dept. of Chemistry, University of Hamburg, Martin Luther King Pl 6, 20146, Hamburg, Germany
| | | |
Collapse
|
8
|
Amberchan G, Snelling RA, Moya E, Landi M, Lutz K, Gatihi R, Singaram B. Reaction of Diisobutylaluminum Borohydride, a Binary Hydride, with Selected Organic Compounds Containing Representative Functional Groups. J Org Chem 2021; 86:6207-6227. [PMID: 33843216 DOI: 10.1021/acs.joc.0c03062] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The binary hydride, diisobutylaluminum borohydride [(iBu)2AlBH4], synthesized from diisobutylaluminum hydride (DIBAL) and borane dimethyl sulfide (BMS) has shown great potential in reducing a variety of organic functional groups. This unique binary hydride, (iBu)2AlBH4, is readily synthesized, versatile, and simple to use. Aldehydes, ketones, esters, and epoxides are reduced very fast to the corresponding alcohols in essentially quantitative yields. This binary hydride can reduce tertiary amides rapidly to the corresponding amines at 25 °C in an efficient manner. Furthermore, nitriles are converted into the corresponding amines in essentially quantitative yields. These reactions occur under ambient conditions and are completed in an hour or less. The reduction products are isolated through a simple acid-base extraction and without the use of column chromatography. Further investigation showed that (iBu)2AlBH4 has the potential to be a selective hydride donor as shown through a series of competitive reactions. Similarities and differences between (iBu)2AlBH4, DIBAL, and BMS are discussed.
Collapse
Affiliation(s)
- Gabriella Amberchan
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, United States
| | - Rachel A Snelling
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, United States
| | - Enrique Moya
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, United States
| | - Madison Landi
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, United States
| | - Kyle Lutz
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, United States
| | - Roxanne Gatihi
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, United States
| | - Bakthan Singaram
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, United States
| |
Collapse
|
9
|
Lauro FV, Francisco DC, Marcela RN, Maria LR, Alejandra GEE, Virginia MA, Yazmin OA. Effective synthesis of a hexacyclic-steroid derivative from 4-hydroxyestrone. Steroids 2020; 163:108715. [PMID: 32853676 DOI: 10.1016/j.steroids.2020.108715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 08/08/2020] [Accepted: 08/17/2020] [Indexed: 11/22/2022]
Abstract
Several studies have been reported for the preparation of hexacyclic-steroid derivatives; however, some reagents are expensive and require special conditions for handling. In this way, the objective of this study was to synthesize a hexacyclic-steroid derivative from 4-hydroxyestrone. The chemical structure was evaluated through both 1H NMR and 13C NMR spectroscopic analysis. The results showed good performance of the hexacyclic-steroid derivative. In conclusion in this study, an easy method for the preparation of the hexacyclic-steroid derivative is reported.
Collapse
Affiliation(s)
- Figueroa-Valverde Lauro
- Laboratory of Pharmaco-Chemistry at the Faculty of Chemical Biological Sciences of the University Autonomous of Campeche, Av. Ex Hacienda Kalá s/n, 24085 San Francisco de Campeche, Mexico.
| | - Diaz Cedillo Francisco
- Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, Prol. Carpio y Plan de Ayala s/n Col. Santo Tomas, Mexico, D.F. C.P. 11340, Mexico
| | - Rosas-Nexticapa Marcela
- Facultad de Nutrición, Universidad Veracruzana, Médicos y Odontólogos s/n, 91010, Xalapa, Veracruz, Mexico.
| | - Lopez-Ramos Maria
- Laboratory of Pharmaco-Chemistry at the Faculty of Chemical Biological Sciences of the University Autonomous of Campeche, Av. Ex Hacienda Kalá s/n, 24085 San Francisco de Campeche, Mexico
| | | | - Mateu-Armand Virginia
- Facultad de Nutrición, Universidad Veracruzana, Médicos y Odontólogos s/n, 91010, Xalapa, Veracruz, Mexico
| | - Ortiz-Ake Yazmin
- Laboratory of Pharmaco-Chemistry at the Faculty of Chemical Biological Sciences of the University Autonomous of Campeche, Av. Ex Hacienda Kalá s/n, 24085 San Francisco de Campeche, Mexico
| |
Collapse
|
10
|
Synthesis of 2′,3′,4′-triaryl-5,6-dihydro-8H-spiro[indolizine-7,5′-isoxazolidin]-8-ones via 1,3-dipolar cycloaddition reaction involving (Z)-C-aryl-N-phenylnitrones. Chem Heterocycl Compd (N Y) 2020. [DOI: 10.1007/s10593-020-02774-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
11
|
Abstract
An operationally facile hydroboration of nitriles is reported that utilizes the stable and inexpensive catalyst LiN(SiMe3)2. The reaction displayed good tolerance of functional groups and also converted carbonyl derivatives.
Collapse
Affiliation(s)
- Pradip Ghosh
- Department of Chemistry
- University of Hamburg
- Martin-Luther-King-Platz 6
- 20146 Hamburg
- Germany
| | | |
Collapse
|
12
|
Lévay K, Hegedűs L. Recent Achievements in the Hydrogenation of Nitriles Catalyzed by Transitional Metals. CURR ORG CHEM 2019. [DOI: 10.2174/1385272823666191007160341] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Amines are important and valuable intermediates in the pharmaceutical, plastic
and agrochemical industry. Hence, there is an increasing interest in developing improved
process for the synthesis of amines. The heterogeneous catalytic hydrogenation of nitriles
is one of the most frequently applied methods for the synthesis of diverse amines, but the
homogeneous catalysis has also received a growing attention from the catalysis
community. This mini-review provides an overview of the recent achievements in the selective
reduction of nitriles using both homogeneous and heterogeneous transition metal
catalysts.
Collapse
Affiliation(s)
- Krisztina Lévay
- Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, 1111 Budapest, Hungary
| | - László Hegedűs
- Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, 1111 Budapest, Hungary
| |
Collapse
|
13
|
Hou SF, Chen JY, Xue M, Jia M, Zhai X, Liao RZ, Tung CH, Wang W. Cooperative Molybdenum-Thiolate Reactivity for Transfer Hydrogenation of Nitriles. ACS Catal 2019. [DOI: 10.1021/acscatal.9b04455] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Shu-Fen Hou
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, No. 27 South Shanda Road, Jinan, 250100, China
| | - Jia-Yi Chen
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, 430074, China
| | - Minghui Xue
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, No. 27 South Shanda Road, Jinan, 250100, China
| | - Mengjing Jia
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, No. 27 South Shanda Road, Jinan, 250100, China
| | - Xiaofang Zhai
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, No. 27 South Shanda Road, Jinan, 250100, China
| | - Rong-Zhen Liao
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, 430074, China
| | - Chen-Ho Tung
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, No. 27 South Shanda Road, Jinan, 250100, China
| | - Wenguang Wang
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, No. 27 South Shanda Road, Jinan, 250100, China
| |
Collapse
|
14
|
Bhattacharjee J, Harinath A, Sarkar A, Panda TK. Polymerization of ϵ‐Caprolactam to Nylon‐6 Catalyzed by Barium σ‐Borane Complex under Mild Condition. ChemCatChem 2019. [DOI: 10.1002/cctc.201900920] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jayeeta Bhattacharjee
- Department of ChemistryIndian Institute of Technology Hyderabad Kandi- 502 285, Sangareddy, Telangana India
| | - Adimulam Harinath
- Department of ChemistryIndian Institute of Technology Hyderabad Kandi- 502 285, Sangareddy, Telangana India
| | - Alok Sarkar
- Momentive Performance Materials Pvt. Ltd. Survey No. 09 Hosur Road, Electronic City (West) Bangalore- 560100 India
| | - Tarun K. Panda
- Department of ChemistryIndian Institute of Technology Hyderabad Kandi- 502 285, Sangareddy, Telangana India
| |
Collapse
|
15
|
Saha S, Eisen MS. Catalytic Recycling of a Th–H Bond via Single or Double Hydroboration of Inactivated Imines or Nitriles. ACS Catal 2019. [DOI: 10.1021/acscatal.9b01399] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Sayantani Saha
- Schulich Faculty of Chemistry, Technion—Israel Institute of Technology, Haifa City 32000, Israel
| | - Moris S. Eisen
- Schulich Faculty of Chemistry, Technion—Israel Institute of Technology, Haifa City 32000, Israel
| |
Collapse
|
16
|
Abstract
Abstract
This review focuses on the selective catalytic hydrogenation of nitriles to primary amines both homogeneously and heterogeneously with transition metal-based catalysts in the view of nitriles as hydrogen carriers. Nitriles can be reduced with two equivalents of H2 to primary amines, thus having a great potential to serve as liquid organic hydrogen carriers (LOHCs) for hydrogen storage. Imines are intermediates in the hydrogenation of nitriles to amines, thus they can also serve as potential LOHCs, however with a lower hydrogen storage capacity (HSC).
Collapse
|
17
|
Ding Y, Luo S, Adijiang A, Zhao H, An J. Reductive Deuteration of Nitriles: The Synthesis of α,α-Dideuterio Amines by Sodium-Mediated Electron Transfer Reactions. J Org Chem 2018; 83:12269-12274. [PMID: 30091922 DOI: 10.1021/acs.joc.8b01730] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The first general reductive deuteration of nitriles under single-electron transfer conditions has been developed for the synthesis of α,α-dideuterio amines. This practical and cost-efficient protocol requires only bench stable and commercially available sodium dispersions and EtOD- d1 and allows for the reductive deuteration of a variety of nitriles in excellent yields and deuterium incorporations.
Collapse
Affiliation(s)
- Yuxuan Ding
- College of Science , China Agricultural University , No. 2 Yuanmingyuan West Road , Beijing 100193 , China
| | - Shihui Luo
- College of Science , China Agricultural University , No. 2 Yuanmingyuan West Road , Beijing 100193 , China
| | - Adila Adijiang
- College of Science , China Agricultural University , No. 2 Yuanmingyuan West Road , Beijing 100193 , China
| | - Hongye Zhao
- College of Science , China Agricultural University , No. 2 Yuanmingyuan West Road , Beijing 100193 , China
| | - Jie An
- College of Science , China Agricultural University , No. 2 Yuanmingyuan West Road , Beijing 100193 , China
| |
Collapse
|
18
|
Lu Z, Cherepakhin V, Demianets I, Lauridsen PJ, Williams TJ. Iridium-based hydride transfer catalysts: from hydrogen storage to fine chemicals. Chem Commun (Camb) 2018; 54:7711-7724. [PMID: 29888372 PMCID: PMC6039230 DOI: 10.1039/c8cc03412e] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Selective hydrogen transfer remains a central research focus in catalysis: hydrogenation and dehydrogenation have central roles, both historical and contemporary, in all aspects of fuel, agricultural, pharmaceutical, and fine chemical synthesis. Our lab has been involved in this area by designing homogeneous catalysts for dehydrogenation and hydrogen transfer that fill needs ranging from on-demand hydrogen storage to fine chemical synthesis. A keen eye toward mechanism has enabled us to develop systems with excellent selectivity and longevity and demonstrate these in a diversity of high-value applications. Here we describe recent work from our lab in these areas that are linked by a central mechanistic trichotomy of catalyst initiation pathways that lead highly analogous precursors to a diversity of useful applications.
Collapse
Affiliation(s)
- Zhiyao Lu
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, 837 Bloom Walk, Los Angeles, CA 90089-1661, USA.
| | | | | | | | | |
Collapse
|
19
|
Takao T, Horikoshi S, Kawashima T, Asano S, Takahashi Y, Sawano A, Suzuki H. Catalytic Hydrogenation of Benzonitrile by Triruthenium Clusters: Consecutive Transformations of Benzonitrile on the Face of a Ru3 Plane. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00165] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Toshiro Takao
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8552, Japan
- JST, ACT-C, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Sachie Horikoshi
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Takashi Kawashima
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Sachio Asano
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Yuta Takahashi
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Akira Sawano
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Hiroharu Suzuki
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8552, Japan
| |
Collapse
|
20
|
Lu Z, Cherepakhin V, Kapenstein T, Williams TJ. Upgrading Biodiesel from Vegetable Oils by Hydrogen Transfer to its Fatty Esters. ACS SUSTAINABLE CHEMISTRY & ENGINEERING 2018; 6:5749-5753. [PMID: 30319930 PMCID: PMC6178228 DOI: 10.1021/acssuschemeng.8b00653] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Conversion of vegetable-derived triglycerides to fatty acid methyl esters (FAMEs) is a popular approach to the generation of biodiesel fuels and the basis of a growing industry. Drawbacks of the strategy are that (a) the glycerol backbone of the triglyceride is discarded as waste, and (2) most available natural triglycerides in the U.S. are multi-unsaturated or fully saturated, giving inferior fuel performance and causing engine problems. Here we show that catalysis by iridium complex 1 can address both of these problems through selective reduction of triglycerides high in polyunsaturation. This is realized using hydrogen from methanol or those imbedded in the triglyceride backbone, concurrently generating lactate as a value-added C3 product. Additional methanol or glycerol as a hydrogen source enables reduction of corn and soybean oils to > 80% oleate. The cost of the iridium catalyst is mitigated by its recovery through aqueous extraction. The process can be further driven with a supporting iron-based catalyst for the complete saturation of all olefins. Preparative procedures are established for synthesis and separation of methyl esters of the hydrogenated fatty acids, enabling instant access to upgraded biofuels.
Collapse
|
21
|
Tokmic K, Jackson BJ, Salazar A, Woods TJ, Fout AR. Cobalt-Catalyzed and Lewis Acid-Assisted Nitrile Hydrogenation to Primary Amines: A Combined Effort. J Am Chem Soc 2017; 139:13554-13561. [PMID: 28906106 DOI: 10.1021/jacs.7b07368] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The selective hydrogenation of nitriles to primary amines using a bench-stable cobalt precatalyst under 4 atm of H2 is reported herein. The catalyst precursor was reduced in situ using NaHBEt3, and the resulting Lewis acid formed, BEt3, was found to be integral to the observed catalysis. Mechanistic insights gleaned from para-hydrogen induced polarization (PHIP) transfer NMR studies revealed that the pairwise hydrogenation of nitriles proceeded through a Co(I/III) redox process.
Collapse
Affiliation(s)
- Kenan Tokmic
- School of Chemical Sciences, University of Illinois at Urbana-Champaign , 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Bailey J Jackson
- School of Chemical Sciences, University of Illinois at Urbana-Champaign , 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Andrea Salazar
- School of Chemical Sciences, University of Illinois at Urbana-Champaign , 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Toby J Woods
- School of Chemical Sciences, University of Illinois at Urbana-Champaign , 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Alison R Fout
- School of Chemical Sciences, University of Illinois at Urbana-Champaign , 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| |
Collapse
|
22
|
Hydrogenation of heteroaromatic nitriles and aromatic dinitriles by heterogeneous or homogeneous ruthenium catalysts derived from [Ru 3 (CO) 12 ]. Inorganica Chim Acta 2017. [DOI: 10.1016/j.ica.2017.04.051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
23
|
Beguerie M, Faradji C, Vendier L, Sabo-Etienne S, Alcaraz G. Ruthenium-Catalyzed Tandem Activation of C≡N and B−H Bonds under Dihydrogen: Synthesis of BN Heterocycles. ChemCatChem 2017. [DOI: 10.1002/cctc.201700682] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Marion Beguerie
- CNRS, LCC, Laboratoire de Chimie de Coordination and; Université de Toulouse, UPS, INPT; F-31077 Toulouse Cedex 4 France
| | - Charly Faradji
- CNRS, LCC, Laboratoire de Chimie de Coordination and; Université de Toulouse, UPS, INPT; F-31077 Toulouse Cedex 4 France
| | - Laure Vendier
- CNRS, LCC, Laboratoire de Chimie de Coordination and; Université de Toulouse, UPS, INPT; F-31077 Toulouse Cedex 4 France
| | - Sylviane Sabo-Etienne
- CNRS, LCC, Laboratoire de Chimie de Coordination and; Université de Toulouse, UPS, INPT; F-31077 Toulouse Cedex 4 France
| | - Gilles Alcaraz
- UMR 6226 CNRS; Université de Rennes 1; Institut des Sciences Chimiques de Rennes, Team “Organometallics:Materials and Catalysis”; Campus de Beaulieu 35042 Rennes, Cedex France
| |
Collapse
|
24
|
Zhang X, Kam L, Trerise R, Williams TJ. Ruthenium-Catalyzed Ammonia Borane Dehydrogenation: Mechanism and Utility. Acc Chem Res 2017; 50:86-95. [PMID: 28032510 DOI: 10.1021/acs.accounts.6b00482] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
One of the greatest challenges in using H2 as a fuel source is finding a safe, efficient, and inexpensive method for its storage. Ammonia borane (AB) is a solid hydrogen storage material that has garnered attention for its high hydrogen weight density (19.6 wt %) and ease of handling and transport. Hydrogen release from ammonia borane is mediated by either hydrolysis, thus giving borate products that are difficult to rereduce, or direct dehydrogenation. Catalytic AB dehydrogenation has thus been a popular topic in recent years, motivated both by applications in hydrogen storage and main group synthetic chemistry. This Account is a complete description of work from our laboratory in ruthenium-catalyzed ammonia borane dehydrogenation over the last 6 years, beginning with the Shvo catalyst and resulting ultimately in the development of optimized, leading catalysts for efficient hydrogen release. We have studied AB dehydrogenation with Shvo's catalyst extensively and generated a detailed understanding of the role that borazine, a dehydrogenation product, plays in the reaction: it is a poison for both Shvo's catalyst and PEM fuel cells. Through independent syntheses of Shvo derivatives, we found a protective mechanism wherein catalyst deactivation by borazine is prevented by coordination of a ligand that might otherwise be a catalytic poison. These studies showed how a bidentate N-N ligand can transform the Shvo into a more reactive species for AB dehydrogenation that minimizes accumulation of borazine. Simultaneously, we designed novel ruthenium catalysts that contain a Lewis acidic boron to replace the Shvo -OH proton, thus offering more flexibility to optimize hydrogen release and take on more general problems in hydride abstraction. Our scorpionate-ligated ruthenium species (12) is a best-of-class catalyst for homogeneous dehydrogenation of ammonia borane in terms of its extent of hydrogen release (4.6 wt %), air tolerance, and reusability. Moreover, a synthetically simplified ruthenium complex supported by the inexpensive bis(pyrazolyl)borate ligand is a comparably good catalyst for AB dehydrogenation, among other reactions. In this Account, we present a detailed, concise description of how our work with the Shvo system progressed to the development of our very reactive and flexible dual-site boron-ruthenium catalysts.
Collapse
Affiliation(s)
- Xingyue Zhang
- Loker Hydrocarbon Research
Institute, Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - Lisa Kam
- Loker Hydrocarbon Research
Institute, Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - Ryan Trerise
- Loker Hydrocarbon Research
Institute, Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - Travis J. Williams
- Loker Hydrocarbon Research
Institute, Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| |
Collapse
|
25
|
Kaithal A, Chatterjee B, Gunanathan C. Ruthenium-Catalyzed Selective Hydroboration of Nitriles and Imines. J Org Chem 2016; 81:11153-11161. [DOI: 10.1021/acs.joc.6b02122] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Akash Kaithal
- School of Chemical Sciences,
National Institute of Science Education and Research (NISER), HBNI, Bhubaneswar 752 050, India
| | - Basujit Chatterjee
- School of Chemical Sciences,
National Institute of Science Education and Research (NISER), HBNI, Bhubaneswar 752 050, India
| | - Chidambaram Gunanathan
- School of Chemical Sciences,
National Institute of Science Education and Research (NISER), HBNI, Bhubaneswar 752 050, India
| |
Collapse
|
26
|
Lu Z, Williams TJ. Di(carbene)-Supported Nickel Systems for CO2 Reduction Under Ambient Conditions. ACS Catal 2016. [DOI: 10.1021/acscatal.6b02101] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Zhiyao Lu
- Donald P. and Katherine B.
Loker Hydrocarbon Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - Travis J. Williams
- Donald P. and Katherine B.
Loker Hydrocarbon Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| |
Collapse
|
27
|
Bhunya S, Roy L, Paul A. Mechanistic Details of Ru–Bis(pyridyl)borate Complex Catalyzed Dehydrogenation of Ammonia–Borane: Role of the Pendant Boron Ligand in Catalysis. ACS Catal 2016. [DOI: 10.1021/acscatal.5b02616] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sourav Bhunya
- Raman Centre for Atomic,
Molecular and Optical Sciences, Indian Association for the Cultivation of Science, Kolkata 700 032, India
| | - Lisa Roy
- Raman Centre for Atomic,
Molecular and Optical Sciences, Indian Association for the Cultivation of Science, Kolkata 700 032, India
| | - Ankan Paul
- Raman Centre for Atomic,
Molecular and Optical Sciences, Indian Association for the Cultivation of Science, Kolkata 700 032, India
| |
Collapse
|
28
|
Zhang X, Kam L, Williams TJ. Dehydrogenation of ammonia borane through the third equivalent of hydrogen. Dalton Trans 2016; 45:7672-7. [PMID: 27052687 DOI: 10.1039/c6dt00604c] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Ammonia borane (AB) has high hydrogen density (19.6 wt%), and can, in principle, release up to 3 equivalents of H2 under mild catalytic conditions. A limited number of catalysts are capable of non-hydrolytic dehydrogenation of AB beyond 2 equivalents of H2 under mild conditions, but none of these is shown directly to derivatise borazine, the product formed after 2 equivalents of H2 are released. We present here a high productivity ruthenium-based catalyst for non-hydrolytic AB dehydrogenation that is capable of borazine dehydrogenation, and thus exhibits among the highest H2 productivity reported to date for anhydrous AB dehydrogenation. At 1 mol% loading, (phen)Ru(OAc)2(CO)2 () effects AB dehydrogenation through 2.7 equivalents of H2 at 70 °C, is robust through multiple charges of AB, and is water and air stable. We further demonstrate that catalyst has the ability both to dehydrogenate borazine in isolation and dehydrogenate AB itself. This is important, both because borazine derivatisation is productivity-limiting in AB dehydrogenation and because borazine is a fuel cell poison that is commonly released in H2 production from this medium.
Collapse
Affiliation(s)
- Xingyue Zhang
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, USA.
| | - Lisa Kam
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, USA.
| | - Travis J Williams
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, USA.
| |
Collapse
|
29
|
Baum RR, Myers WK, Greer SM, Breece RM, Tierney DL. The Original CoII Heteroscorpionates Revisited: On the EPR of Pseudotetrahedral CoII. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201501356] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Robert R. Baum
- Department of Chemistry and BiochemistryMiami University45056OxfordOHUSA
| | - William K. Myers
- Department of Chemistry and BiochemistryMiami University45056OxfordOHUSA
| | - Samuel M. Greer
- Department of Chemistry and BiochemistryMiami University45056OxfordOHUSA
| | - Robert M. Breece
- Department of Chemistry and BiochemistryMiami University45056OxfordOHUSA
| | - David L. Tierney
- Department of Chemistry and BiochemistryMiami University45056OxfordOHUSA
| |
Collapse
|
30
|
Drover MW, Schafer LL, Love JA. Capturing HBCy2
: Using N,O-Chelated Complexes of Rhodium(I) and Iridium(I) for Chemoselective Hydroboration. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201511448] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Marcus W. Drover
- Department of Chemistry; The University of British Columbia; Vancouver BC V6T 1Z1 Canada
| | - Laurel L. Schafer
- Department of Chemistry; The University of British Columbia; Vancouver BC V6T 1Z1 Canada
| | - Jennifer A. Love
- Department of Chemistry; The University of British Columbia; Vancouver BC V6T 1Z1 Canada
| |
Collapse
|
31
|
Drover MW, Schafer LL, Love JA. Capturing HBCy2: Using N,O-Chelated Complexes of Rhodium(I) and Iridium(I) for Chemoselective Hydroboration. Angew Chem Int Ed Engl 2016; 55:3181-6. [PMID: 26847809 DOI: 10.1002/anie.201511448] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Indexed: 01/12/2023]
Abstract
1,3-N,O-chelated complexes of Rh(I) and Ir(I) cooperatively and reversibly stabilized the B-H bond of HBCy2 to afford six-membered metallaheterocycles (M=Rh (7) or Ir (8)) having a δ-[M]⋅⋅⋅H-B agostic interaction. Treatment of these Shimoi-type borane adducts 7 or 8 with both an aldehyde and an alkene resulted in chemoselective aldehyde hydroboration and reformation of the 1,3-N,O-chelated starting material. The observed chemoselectivity is inverted from that of free HBCy2 , which is selective for alkene hydroboration.
Collapse
Affiliation(s)
- Marcus W Drover
- Department of Chemistry, The University of British Columbia, Vancouver, BC, V6T 1Z1, Canada
| | - Laurel L Schafer
- Department of Chemistry, The University of British Columbia, Vancouver, BC, V6T 1Z1, Canada.
| | - Jennifer A Love
- Department of Chemistry, The University of British Columbia, Vancouver, BC, V6T 1Z1, Canada.
| |
Collapse
|
32
|
Pal S, Drover MW, Patrick BO, Love JA. Enhancing Reactivity of Directly íObservable B-H-Pt Interactions through Conformational Rigidity. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201501305] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Shrinwantu Pal
- Department of Chemistry; The University of British Columbia; 2036 Main Mall V6T 1Z1 Vancouver BC Canada
| | - Marcus W. Drover
- Department of Chemistry; The University of British Columbia; 2036 Main Mall V6T 1Z1 Vancouver BC Canada
| | - Brian O. Patrick
- Department of Chemistry; The University of British Columbia; 2036 Main Mall V6T 1Z1 Vancouver BC Canada
| | - Jennifer A. Love
- Department of Chemistry; The University of British Columbia; 2036 Main Mall V6T 1Z1 Vancouver BC Canada
| |
Collapse
|
33
|
Weetman C, Anker MD, Arrowsmith M, Hill MS, Kociok-Köhn G, Liptrot DJ, Mahon MF. Magnesium-catalysed nitrile hydroboration. Chem Sci 2016; 7:628-641. [PMID: 29896350 PMCID: PMC5952893 DOI: 10.1039/c5sc03114a] [Citation(s) in RCA: 136] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 10/19/2015] [Indexed: 01/17/2023] Open
Abstract
A β-diketiminato n-butylmagnesium complex is presented as a selective precatalyst for the reductive hydroboration of organic nitriles with pinacolborane (HBpin). Stoichiometric reactivity studies indicate that catalytic turnover ensues through the generation of magnesium aldimido, aldimidoborate and borylamido intermediates, which are formed in a sequence of intramolecular nitrile insertion and inter- and intramolecular B-H metathesis events. Kinetic studies highlight variations in mechanism for the catalytic dihydroboration of alkyl nitriles, aryl nitriles bearing electron withdrawing (Ar(EWG)CN) and aryl nitriles bearing electron donating (Ar(EDG)CN) substitution patterns. Kinetic isotope effects (KIEs) for catalysis performed with DBpin indicate that B-H bond breaking and C-H bond forming reactions are involved in the rate determining processes during the dihydroboration of alkyl nitriles and Ar(EDG)CN substrates, which display divergent first and second order rate dependences on [HBpin] respectively. In contrast, the hydroboration of Ar(EWG)CN substrates provides no KIE and HBpin is not implicated in the rate determining process during catalysis. Irrespective of these differences, a common mechanism is proposed in which the rate determining steps are deduced to vary through the establishment of several pre-equilibria, the relative positions of which are determined by the respective stabilities of the dimeric and monomeric magnesium aldimide and magnesium aldimidoborate intermediates as a result of adjustments to the basicity of the nitrile substrate. More generally, these observations indicate that homogeneous processes performed under heavier alkaline earth catalysis are likely to demonstrate previously unappreciated mechanistic diversity.
Collapse
Affiliation(s)
- Catherine Weetman
- Department of Chemistry , University of Bath , Claverton Down , Bath , BA2 7AY , UK .
| | - Mathew D Anker
- Department of Chemistry , University of Bath , Claverton Down , Bath , BA2 7AY , UK .
| | - Merle Arrowsmith
- Department of Chemistry , University of Bath , Claverton Down , Bath , BA2 7AY , UK .
| | - Michael S Hill
- Department of Chemistry , University of Bath , Claverton Down , Bath , BA2 7AY , UK .
| | - Gabriele Kociok-Köhn
- Department of Chemistry , University of Bath , Claverton Down , Bath , BA2 7AY , UK .
| | - David J Liptrot
- Department of Chemistry , University of Bath , Claverton Down , Bath , BA2 7AY , UK .
| | - Mary F Mahon
- Department of Chemistry , University of Bath , Claverton Down , Bath , BA2 7AY , UK .
| |
Collapse
|
34
|
Geri JB, Szymczak NK. A Proton-Switchable Bifunctional Ruthenium Complex That Catalyzes Nitrile Hydroboration. J Am Chem Soc 2015; 137:12808-14. [DOI: 10.1021/jacs.5b08406] [Citation(s) in RCA: 143] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Jacob B. Geri
- Department of Chemistry, University of Michigan, 930 N. University, Ann Arbor, Michigan 48109-1055, United States
| | - Nathaniel K. Szymczak
- Department of Chemistry, University of Michigan, 930 N. University, Ann Arbor, Michigan 48109-1055, United States
| |
Collapse
|
35
|
Zhang X, Lu Z, Foellmer LK, Williams TJ. Nitrogen-Based Ligands Accelerate Ammonia Borane Dehydrogenation with the Shvo Catalyst. Organometallics 2015. [DOI: 10.1021/acs.organomet.5b00409] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Xingyue Zhang
- Loker Hydrocarbon Research
Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - Zhiyao Lu
- Loker Hydrocarbon Research
Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - Lena K. Foellmer
- Loker Hydrocarbon Research
Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - Travis J. Williams
- Loker Hydrocarbon Research
Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| |
Collapse
|
36
|
Cowie BE, Emslie DJH. Bis-hydrocarbyl Platinum(II) Ambiphilic Ligand Complexes: Alkyl–Aryl Exchange between Platinum and Boron. Organometallics 2015. [DOI: 10.1021/om501269x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Bradley E. Cowie
- Department of Chemistry and
Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
| | - David J. H. Emslie
- Department of Chemistry and
Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
| |
Collapse
|
37
|
Bagal DB, Bhanage BM. Recent Advances in Transition Metal-Catalyzed Hydrogenation of Nitriles. Adv Synth Catal 2015. [DOI: 10.1002/adsc.201400940] [Citation(s) in RCA: 163] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
38
|
Abubekerov M, Diaconescu PL. Synthesis and characterization of ferrocene-chelating heteroscorpionate complexes of nickel(II) and zinc(II). Inorg Chem 2015; 54:1778-84. [PMID: 25607817 DOI: 10.1021/ic502691b] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The first example of a ferrocene-chelating heteroscorpionate, [Li(THF)2][fc(PPh2)(BH[(3,5-Me)2pz]2)] ((fc(P,B))Li(THF)2, fc = 1,1'-ferrocenediyl) is described. Starting from a previously reported compound, fcBr(PPh2), a series of ferrocene derivatives, fc(PPh2)(B[OMe]2), [Li(OEt2)][fc(PPh2)(BH3)], [Li(THF)2][fc(PPh2)(BH[(3,5-Me)2pz]2)] (pz = pyrazole), was isolated and characterized. Compound (fc(P,B))Li(THF)2 allowed the synthesis of the corresponding nickel and zinc complexes, (fc(P,B))NiCl, (fc(P,B))NiMe, (fc(P,B))ZnCl, and (fc(P,B))ZnMe. All compounds were characterized by NMR spectroscopy, while the zinc and nickel complexes were also characterized by X-ray crystallography. The redox behavior of (fc(P,B))NiCl, (fc(P,B))NiMe, (fc(P,B))ZnCl, and (fc(P,B))ZnMe was studied by cyclic voltammetry and supported by density functional theory calculations.
Collapse
Affiliation(s)
- Mark Abubekerov
- Department of Chemistry and Biochemistry, University of California , Los Angeles, California 90095, United States
| | | |
Collapse
|
39
|
Pennington-Boggio MK, Conley BL, Richmond MG, Williams TJ. Synthesis, Structure, and Conformational Dynamics of Rhodium and Iridium Complexes of Dimethylbis(2-pyridyl)borate. Polyhedron 2014; 84:24-31. [PMID: 25435645 DOI: 10.1016/j.poly.2014.05.042] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Rhodium(I) and Iridium(I) borate complexes of the structure [Me2B(2-py)2]ML2 (L2 = (tBuNC)2, (CO)2, (C2H4)2, cod, dppe) were prepared and structurally characterized (cod = 1,5-cyclooctadiene; dppe = 1,2-diphenylphosphinoethane). Each contains a boat-configured chelate ring that participates in a boat-to-boat ring flip. Computational evidence shows that the ring flip proceeds through a transition state that is near planarity about the chelate ring. We observe an empirical, quantitative correlation between the barrier of this ring flip and the π acceptor ability of the ancillary ligand groups on the metal. The ring flip barrier correlates weakly to the Tolman and Lever ligand parameterization schemes, apparently because these combine both σ and π effects while we propose that the ring flip barrier is dominated by π bonding. This observation is consistent with metal-ligand π interactions becoming temporarily available only in the near-planar transition state of the chelate ring flip and not the boat-configured ground state. Thus, this is a first-of-class observation of metal-ligand π bonding governing conformational dynamics.
Collapse
Affiliation(s)
- Megan K Pennington-Boggio
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661
| | - Brian L Conley
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661
| | - Michael G Richmond
- Department of Chemistry, University of North Texas, Denton, Texas 76203,
| | - Travis J Williams
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661
| |
Collapse
|
40
|
Thiol-ene coupling: An efficient tool for the synthesis of new biobased aliphatic amines for epoxy curing. POLYMER 2014. [DOI: 10.1016/j.polymer.2014.07.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
41
|
Celaje JA, Pennington-Boggio MK, Flaig RW, Richmond MG, Williams TJ. Synthesis and Characterization of Dimethylbis(2-pyridyl)borate Nickel(II) Complexes: Unimolecular Square-Planar to Square-Planar Rotation around Nickel(II). Organometallics 2014; 33:2019-2026. [PMID: 24882919 PMCID: PMC4034079 DOI: 10.1021/om500173j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Indexed: 11/29/2022]
Abstract
The syntheses of novel dimethylbis(2-pyridyl)borate nickel(II) complexes 4 and 6 are reported. These complexes were unambiguously characterized by X-ray analysis. In dichloromethane solvent, complex 4 undergoes a unique square-planar to square-planar rotation around the nickel(II) center, for which activation parameters of ΔH⧧ = 12.2(1) kcal mol-1 and ΔS⧧ = 0.8(5) eu were measured via NMR inversion recovery experiments. Complex 4 was also observed to isomerize via a relatively slow ring flip: ΔH⧧ = 15.0(2) kcal mol-1; and ΔS⧧ = -4.2(7) eu. DFT studies support the experimentally measured rotation activation energy (cf. calculated ΔH⧧ = 11.1 kcal mol-1) as well as the presence of a high-energy triplet intermediate (ΔH = 8.8 kcal mol-1).
Collapse
Affiliation(s)
- Jeff A Celaje
- Loker Hydrocarbon Institute and Department of Chemistry, University of Southern California , Los Angeles, California, 90089-1661, United States
| | - Megan K Pennington-Boggio
- Loker Hydrocarbon Institute and Department of Chemistry, University of Southern California , Los Angeles, California, 90089-1661, United States
| | - Robinson W Flaig
- Loker Hydrocarbon Institute and Department of Chemistry, University of Southern California , Los Angeles, California, 90089-1661, United States
| | - Michael G Richmond
- Department of Chemistry, University of North Texas , Denton, Texas, 76203-5017, United States
| | - Travis J Williams
- Loker Hydrocarbon Institute and Department of Chemistry, University of Southern California , Los Angeles, California, 90089-1661, United States
| |
Collapse
|