1
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Podchorodecka P, Dziuk B, Szostak R, Szostak M, Bisz E. IPr* Oxa - a new class of sterically-hindered, wingtip-flexible N,C-chelating oxazole-donor N-heterocyclic carbene ligands. Dalton Trans 2023; 52:13608-13617. [PMID: 37698540 DOI: 10.1039/d3dt02255b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
N-heterocyclic carbenes (NHCs) have emerged as a major direction in ancillary ligand development for stabilization of reactive metal centers in inorganic and organometallic chemistry. In particular, wingtip-flexible NHCs have attracted significant attention due to their unique ability to provide a sterically-demanding environment for transition metals in various oxidation states. Herein, we report a new class of sterically-hindered, wingtip-flexible NHC ligands that feature N,C-chelating oxazole donors. These ligands are readily accessible through a modular arylation of oxazole derivatives. We report their synthesis and complete structural and electronic characterization. The evaluation of steric, electron-donating and π-accepting properties and coordination chemistry to Ag(I), Pd(II) and Rh(I) is described. Preliminary studies of catalytic activity in Ag, Pd and Rh-catalyzed coupling and hydrosilylation reactions are presented. This study establishes the fluxional behavior of a freely-rotatable oxazole unit, wherein the oxazolyl ring adjusts to the steric and electronic environment of the metal center. Considering the tremendous impact of sterically-hindered NHCs and their potential to stabilize reactive metals by N-chelation, we expect that this class of NHC ligands will be of broad interest in inorganic and organometallic chemistry.
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Affiliation(s)
- Pamela Podchorodecka
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland.
| | - Błażej Dziuk
- Department of Chemistry, University of Science and Technology, Norwida 4/6, Wroclaw 50-373, Poland
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA.
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland.
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2
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Rahman MM, Meng G, Bisz E, Dziuk B, Lalancette R, Szostak R, Szostak M. I tOct (I tOctyl) - pushing the limits of I tBu: highly hindered electron-rich N-aliphatic N-heterocyclic carbenes. Chem Sci 2023; 14:5141-5147. [PMID: 37206400 PMCID: PMC10189875 DOI: 10.1039/d3sc01006f] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 04/15/2023] [Indexed: 05/21/2023] Open
Abstract
ItBu (ItBu = 1,3-di-tert-butylimidazol-2-ylidene) represents the most important and most versatile N-alkyl N-heterocyclic carbene available in organic synthesis and catalysis. Herein, we report the synthesis, structural characterization and catalytic activity of ItOct (ItOctyl), C2-symmetric, higher homologues of ItBu. The new ligand class, including saturated imidazolin-2-ylidene analogues has been commercialized in collaboration with MilliporeSigma: ItOct, 929 298; SItOct, 929 492 to enable broad access of the academic and industrial researchers within the field of organic and inorganic synthesis. We demonstrate that replacement of the t-Bu side chain with t-Oct results in the highest steric volume of N-alkyl N-heterocyclic carbenes reported to date, while retaining the electronic properties inherent to N-aliphatic ligands, such as extremely strong σ-donation crucial to the reactivity of N-alkyl N-heterocyclic carbenes. An efficient large-scale synthesis of imidazolium ItOct and imidazolinium SItOct carbene precursors is presented. Coordination chemistry to Au(i), Cu(i), Ag(i) and Pd(ii) as well as beneficial effects on catalysis using Au(i), Cu(i), Ag(i) and Pd(ii) complexes are described. Considering the tremendous importance of ItBu in catalysis, synthesis and metal stabilization, we anticipate that the new class of ItOct ligands will find wide application in pushing the boundaries of new and existing approaches in organic and inorganic synthesis.
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Affiliation(s)
- Md Mahbubur Rahman
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Guangrong Meng
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Elwira Bisz
- Department of Chemistry, Opole University 48 Oleska Street Opole 45-052 Poland
| | - Błażej Dziuk
- Department of Chemistry, Wroclaw University of Science and Technology Norwida 4/6 14 Wroclaw 50-373 Poland
| | - Roger Lalancette
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Roman Szostak
- Department of Chemistry, Wroclaw University F. Joliot-Curie 14 Wroclaw 50-383 Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
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3
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Gao P, Xu J, Zhou T, Liu Y, Bisz E, Dziuk B, Lalancette R, Szostak R, Zhang D, Szostak M. L-Shaped Heterobidentate Imidazo[1,5-a]pyridin-3-ylidene (N,C)-Ligands for Oxidant-Free Au I /Au III Catalysis. Angew Chem Int Ed Engl 2023; 62:e202218427. [PMID: 36696514 PMCID: PMC9992098 DOI: 10.1002/anie.202218427] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/18/2023] [Accepted: 01/25/2023] [Indexed: 01/26/2023]
Abstract
In the last decade, major advances have been made in homogeneous gold catalysis. However, AuI /AuIII catalytic cycle remains much less explored due to the reluctance of AuI to undergo oxidative addition and the stability of the AuIII intermediate. Herein, we report activation of aryl halides at gold(I) enabled by NHC (NHC=N-heterocyclic carbene) ligands through the development of a new class of L-shaped heterobidentate ImPy (ImPy=imidazo[1,5-a]pyridin-3-ylidene) N,C ligands that feature hemilabile character of the amino group in combination with strong σ-donation of the carbene center in a rigid conformation, imposed by the ligand architecture. Detailed characterization and control studies reveal key ligand features for AuI /AuIII redox cycle, wherein the hemilabile nitrogen is placed at the coordinating position of a rigid framework. Given the tremendous significance of homogeneous gold catalysis, we anticipate that this ligand platform will find widespread application.
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Affiliation(s)
- Pengcheng Gao
- Department of Chemistry, Rutgers University, 73 Warren Street, 07102, Newark, NJ, USA
| | - Jihong Xu
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, Institute of Theoretical Chemistry, School of Chemistry and Chemical Engineering, Shandong University, 250100, Jinan, China
| | - Tongliang Zhou
- Department of Chemistry, Rutgers University, 73 Warren Street, 07102, Newark, NJ, USA
| | - Yanhong Liu
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, Institute of Theoretical Chemistry, School of Chemistry and Chemical Engineering, Shandong University, 250100, Jinan, China
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, 45-052, Opole, Poland
| | - Błażej Dziuk
- Department of Chemistry, University of Science and Technology, Norwida 4/6, 50-373, Wroclaw, Poland
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, 07102, Newark, NJ, USA
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, 50-383, Wroclaw, Poland
| | - Dongju Zhang
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, Institute of Theoretical Chemistry, School of Chemistry and Chemical Engineering, Shandong University, 250100, Jinan, China
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, 07102, Newark, NJ, USA
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4
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Gao P, Xu J, Zhou T, Liu Y, Bisz E, Dziuk B, Lalancette R, Szostak R, Zhang D, Szostak M. Activation of Aryl Halides at Gold(I) by N‐Heterocyclic Carbenes: L‐Shaped Heterobidentate ImPy (Imidazo[1,5‐a]pyridin‐ylidene) N,C Ligands for Oxidant‐Free Au(I)/Au(III) Catalysis. Angew Chem Int Ed Engl 2023. [DOI: 10.1002/ange.202218427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Pengcheng Gao
- Rutgers University New Brunswick Chemistry UNITED STATES
| | - Jihong Xu
- Shandong University School of Chemistry CHINA
| | - Tongliang Zhou
- Rutgers University New Brunswick Chemistry UNITED STATES
| | - Yanhong Liu
- Shandong University School of Chemistry CHINA
| | - Elwira Bisz
- Opole University: Uniwersytet Opolski Chemistry POLAND
| | - Błażej Dziuk
- Wroclaw University of Science and Technology: Politechnika Wroclawska Chemistry POLAND
| | | | - Roman Szostak
- University of Wroclaw: Uniwersytet Wroclawski Chemistry POLAND
| | | | - Michal Szostak
- Rutgers University Department of Chemistry 73 Warren St. 07102 Newark UNITED STATES
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5
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Chu W, Zhou T, Bisz E, Dziuk B, Lalancette R, Szostak R, Szostak M. CAAC-IPr*: easily accessible, highly sterically-hindered cyclic (alkyl)(amino)carbenes. Chem Commun (Camb) 2022; 58:13467-13470. [PMID: 36382995 PMCID: PMC9737351 DOI: 10.1039/d2cc05668b] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
IPr* (IPr* = 1,3-bis(2,6-bis(diphenylmethyl)-4-methylphenyl)imidazol-2-ylidene) has emerged as a powerful highly hindered and sterically-flexible ligand platform for transition-metal catalysis. CAACs (CAAC = cyclic (al-kyl)(amino)carbenes) have gained major attention as strongly electron-rich carbon analogues of NHCs (NHC = N-heterocyclic carbene) with broad applications in both industry and academia. Herein, we report a merger of CAAC ligands with highly-hindered IPr*. The efficient synthesis, electronic characterization and application in model Cu-catalyzed hydroboration of alkynes is described. The ligands are strongly electron-rich, bulky and flexible around the N-Ar wingtip. The availability of various IPr* and CAAC templates offers a significant potential to expand the existing arsenal of NHC ligands to electron-rich bulky architectures with critical applications in metal stabilization and catalysis.
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Affiliation(s)
- Wenchao Chu
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, USA.
| | - Tongliang Zhou
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, USA.
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Błażej Dziuk
- Faculty of Chemistry, Wroclaw University of Science and Technology, 50-370 Wroclaw, Poland
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, USA.
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, USA.
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6
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Zhou T, Gao P, Bisz E, Dziuk B, Lalancette R, Szostak R, Szostak M. Well-Defined, Air- and Moisture-Stable Palladium-Imidazo[1,5- a]pyridin-3-ylidene Complexes: A Versatile Catalyst Platform for Cross-Coupling Reactions by L-Shaped NHC Ligands. Catal Sci Technol 2022; 12:6581-6589. [PMID: 38045636 PMCID: PMC10691866 DOI: 10.1039/d2cy01136k] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
We describe the development of [(NHC)Pd(cinnamyl)Cl] complexes of ImPy (ImPy = imidazo[1,5-a]pyridin-3-ylidene) as a versatile class of precatalysts for cross-coupling reactions. These precatalysts feature fast activation to monoligated Pd(0) with 1:1 Pd to ligand ratio in a rigid imidazo[1,5-a]pyridin-3-ylidene template. Steric matching of the C5-substituent and N2-wingtip in the catalytic pocket of the catalyst framework led to the discovery of ImPyMesDipp as a highly reactive imidazo[1,5-a]pyridin-3-ylidene ligand for Pd-catalyzed cross-coupling of nitroarenes by challenging C-NO2 activation. Kinetic studies demonstrate fast activation and high reactivity of this class of well-defined ImPy-Pd catalysts. Structural studies provide full characteristics of this new class of imidazo[1,5-a]pyridin-3-ylidene ligands. Computational studies establish electronic properties of sterically-restricted imidazo[1,5-a]pyridin-3-ylidene ligands. Finally, a scalable synthesis of C5-substituted imidazo[1,5-a]pyridin-3-ylidene ligands through Ni-catalyzed Kumada cross-coupling is disclosed. The method obviates chromatographic purification at any of the steps, resulting in a facile and modular access to ImPy ligands. We anticipate that well-defined [Pd-ImPy] complexes will find broad utility in organic synthesis and catalysis for activation of unreactive bonds.
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Affiliation(s)
- Tongliang Zhou
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA
| | - Pengcheng Gao
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Błażej Dziuk
- Department of Chemistry, University of Science and Technology, Norwida 4/6, Wroclaw 50-373, Poland
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA
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7
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Rahman MM, Zhang J, Zhao Q, Feliciano J, Bisz E, Dziuk B, Lalancette R, Szostak R, Szostak M. Pd-PEPPSI N-Heterocyclic Carbene Complexes from Caffeine: Application in Suzuki, Heck, and Sonogashira Reactions. Organometallics 2022; 41:2281-2290. [PMID: 38031591 PMCID: PMC10686539 DOI: 10.1021/acs.organomet.2c00262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The first synthesis of Pd-PEPPSI N-heterocyclic carbene complexes derived from the abundant and renewable natural product caffeine is reported. The catalysts bearing 3-chloro-pyridine, pyridine and N-methylimidazole ancillary ligands were readily prepared from the corresponding N9-Me caffeine imidazolium salt by direct deprotonation and coordination to PdX2 in the presence of N-heterocycles or by ligand displacement of PdX2(Het)2. The model Pd-PEPPSI-caffeine complex has been characterized by x-ray crystallography. The complexes were successfully employed in the Suzuki cross-coupling of aryl bromides, Suzuki cross-coupling of amides, Heck cross-coupling and Sonogashira cross-coupling. Computational studies were employed to determine frontier molecular orbitals and bond order analysis of caffeine derived Pd-PEPPSI complexes. This class of catalysts offers an entry to utilize benign and sustainable biomass-derived Xanthine NHC ligands in the popular Pd-PEPPSI systems in organic synthesis and catalysis.
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Affiliation(s)
- Md Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Jin Zhang
- College of Chemistry and Chemical Engineering, Key Laboratory of Chemical Additives for China National Light Industry, Shaanxi University of Science and Technology, Xi'an 710021, China
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Qun Zhao
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Jessica Feliciano
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Błażej Dziuk
- Department of Chemistry, University of Science and Technology, Norwida 4/6, Wroclaw 50-373, Poland
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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8
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Zhang J, Rahman MM, Zhao Q, Feliciano J, Bisz E, Dziuk B, Lalancette R, Szostak R, Szostak M. N-Heterocyclic Carbene Complexes of Nickel(II) from Caffeine and Theophylline: Sustainable Alternative to Imidazol-2-ylidenes. Organometallics 2022; 41:1806-1815. [PMID: 36213557 PMCID: PMC9534456 DOI: 10.1021/acs.organomet.2c00019] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Xanthines, such as caffeine and theophylline, are abundant natural products that are often present in foods. Leveraging renewable and benign resources for ligand design in organometallic chemistry and catalysis is one of the major missions of green and sustainable chemistry. In this Special Issue on Sustainable Organometallic Chemistry, we report the first nickel-N-heterocyclic carbene complexes derived from Xanthines. Well-defined, air- and moisture-stable, half-sandwich, cyclopentadienyl [CpNi(NHC)I] nickel-NHC complexes are prepared from the natural products caffeine and theophylline. The model complex has been characterized by x-ray crystallography. The evaluation of steric, electron-donating and π-accepting properties is presented. High activity in the model Suzuki-Miyaura cross-coupling is demonstrated. The data show that nickel-N-heterocyclic carbenes derived from both Earth abundant 3d transition metal and renewable natural products represent a sustainable alternative to the classical imidazol-2-ylidenes.
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Affiliation(s)
- Jin Zhang
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
- College of Chemistry and Chemical Engineering, Key Laboratory of Chemical Additives for China National Light Industry, Shaanxi University of Science and Technology, Xi’an 710021, P. R. China
| | - Md. Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Qun Zhao
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Jessica Feliciano
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Błażej Dziuk
- Department of Chemistry, University of Science and Technology, Norwida 4/6, Wroclaw 50-373, Poland
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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9
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Wang CA, Rahman MM, Bisz E, Dziuk B, Szostak R, Szostak M. Palladium-NHC (NHC = N-heterocyclic Carbene)-Catalyzed Suzuki–Miyaura Cross-Coupling of Alkyl Amides. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05738] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Chang-An Wang
- College of Chemistry and Chemical Engineering, Taishan University, Tai’an, Shandong 271000, People’s Republic of China
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Md. Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Błażej Dziuk
- Department of Chemistry, University of Science and Technology, Norwida 4/6 14, Wroclaw 50-373, Poland
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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10
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Kardela M, Halikowska-Tarasek K, Szostak M, Bisz E. Enhanced Activity of Bulky N-Heterocylic Carbenes in Nickel–NHC Catalyzed Kumada–Corriu Cross-Coupling of Aryl Tosylates. Catal Sci Technol 2022. [DOI: 10.1039/d2cy01805e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Over the last decades, advances in Ni catalysis have expanded the chemical reactivity of cross-coupling reactions and led to the discovery of catalytic systems that are now widely applied in...
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11
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Bisz E. Iron-Catalyzed Cross-Coupling Reactions of Alkyl Grignards with Aryl Chlorobenzenesulfonates. Molecules 2021; 26:5895. [PMID: 34641439 PMCID: PMC8510395 DOI: 10.3390/molecules26195895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 09/21/2021] [Accepted: 09/24/2021] [Indexed: 11/20/2022] Open
Abstract
Aryl sulfonate esters are versatile synthetic intermediates in organic chemistry as well as attractive architectures due to their bioactive properties. Herein, we report the synthesis of alkyl-substituted benzenesulfonate esters by iron-catalyzed C(sp2)-C(sp3) cross-coupling of Grignard reagents with aryl chlorides. The method operates using an environmentally benign and sustainable iron catalytic system, employing benign urea ligands. A broad range of chlorobenzenesulfonates as well as challenging alkyl organometallics containing β-hydrogens are compatible with these conditions, affording alkylated products in high to excellent yields. The study reveals that aryl sulfonate esters are the most reactive activating groups for iron-catalyzed alkylative C(sp2)-C(sp3) cross-coupling of aryl chlorides with Grignard reagents.
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Affiliation(s)
- Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, 45-052 Opole, Poland
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12
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Rahman MM, Pyle DJ, Bisz E, Dziuk B, Ejsmont K, Lalancette R, Wang Q, Chen H, Szostak R, Szostak M. Evaluation of Cyclic Amides as Activating Groups in N-C Bond Cross-Coupling: Discovery of N-Acyl-δ-valerolactams as Effective Twisted Amide Precursors for Cross-Coupling Reactions. J Org Chem 2021; 86:10455-10466. [PMID: 34275281 DOI: 10.1021/acs.joc.1c01110] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The development of efficient methods for facilitating N-C(O) bond activation in amides is an important objective in organic synthesis that permits the manipulation of the traditionally unreactive amide bonds. Herein, we report a comparative evaluation of a series of cyclic amides as activating groups in amide N-C(O) bond cross-coupling. Evaluation of N-acyl-imides, N-acyl-lactams, and N-acyl-oxazolidinones bearing five- and six-membered rings using Pd(II)-NHC and Pd-phosphine systems reveals the relative reactivity order of N-activating groups in Suzuki-Miyaura cross-coupling. The reactivity of activated phenolic esters and thioesters is evaluated for comparison in O-C(O) and S-C(O) cross-coupling under the same reaction conditions. Most notably, the study reveals N-acyl-δ-valerolactams as a highly effective class of mono-N-acyl-activated amide precursors in cross-coupling. The X-ray structure of the model N-acyl-δ-valerolactam is characterized by an additive Winkler-Dunitz distortion parameter Σ(τ+χN) of 54.0°, placing this amide in a medium distortion range of twisted amides. Computational studies provide insight into the structural and energetic parameters of the amide bond, including amidic resonance, N/O-protonation aptitude, and the rotational barrier around the N-C(O) axis. This class of N-acyl-lactams will be a valuable addition to the growing portfolio of amide electrophiles for cross-coupling reactions by acyl-metal intermediates.
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Affiliation(s)
- Md Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Daniel J Pyle
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Błażej Dziuk
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland.,Department of Chemistry, Wroclaw University of Science and Technology, Norwida 4/6 14, Wroclaw 50-373, Poland
| | - Krzysztof Ejsmont
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Qi Wang
- Department of Chemistry & Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, United States
| | - Hao Chen
- Department of Chemistry & Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, United States
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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13
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Piontek A, Ochędzan‐Siodłak W, Bisz E, Szostak M. Cobalt−NHC Catalyzed C(sp
2
)−C(sp
3
) and C(sp
2
)−C(sp
2
) Kumada Cross‐Coupling of Aryl Tosylates with Alkyl and Aryl Grignard Reagents. ChemCatChem 2020. [DOI: 10.1002/cctc.202001347] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Aleksandra Piontek
- Department of Chemistry Opole University 48 Oleska Street 45-052 Opole Poland
| | | | - Elwira Bisz
- Department of Chemistry Opole University 48 Oleska Street 45-052 Opole Poland
| | - Michal Szostak
- Department of Chemistry Rutgers University 73 Warren Street Newark NJ 07102 USA
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14
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Rahman MM, Liu C, Bisz E, Dziuk B, Lalancette R, Wang Q, Chen H, Szostak R, Szostak M. N-Acyl-glutarimides: Effect of Glutarimide Ring on the Structures of Fully Perpendicular Twisted Amides and N–C Bond Cross-Coupling. J Org Chem 2020; 85:5475-5485. [DOI: 10.1021/acs.joc.0c00227] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Md. Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Chengwei Liu
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Błażej Dziuk
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
- Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-373 Wrocław, Poland
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Qi Wang
- Department of Chemistry & Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, United States
| | - Hao Chen
- Department of Chemistry & Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, United States
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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15
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Affiliation(s)
- Elwira Bisz
- Department of Chemistry Opole University 48 Oleska Street Opole 45-052 Poland
| | - Marlena Kardela
- Department of Chemistry Opole University 48 Oleska Street Opole 45-052 Poland
| | - Michal Szostak
- Department of Chemistry Opole University 48 Oleska Street Opole 45-052 Poland
- Department of Chemistry Rutgers University 73 Warren Street Newark NJ 07102 United States
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16
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Piontek A, Ochędzan‐Siodłak W, Bisz E, Szostak M. Nickel‐Catalyzed C(
sp
2
)−C(
sp
3
) Kumada Cross‐Coupling of Aryl Tosylates with Alkyl Grignard Reagents. Adv Synth Catal 2019. [DOI: 10.1002/adsc.201801586] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Aleksandra Piontek
- Department of Chemistry Opole University 48 Oleska Street Opole 45-052 Poland
| | | | - Elwira Bisz
- Department of Chemistry Opole University 48 Oleska Street Opole 45-052 Poland
| | - Michal Szostak
- College of Chemistry and Chemical Engineering and Key Laboratory of Auxiliary Chemistry and Technology for Chemical Industry, Ministry of Education Shaanxi University of Science and Technology Xi'an 710021 China
- Department of Chemistry Opole University 48 Oleska Street Opole 45-052 Poland
- Department of Chemistry Rutgers University 73 Warren Street Newark NJ 07102 United States
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17
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Bisz E, Podchorodecka P, Szostak M. N
-Methylcaprolactam as a Dipolar Aprotic Solvent for Iron-Catalyzed Cross-Coupling Reactions: Matching Efficiency with Safer Reaction Media. ChemCatChem 2019. [DOI: 10.1002/cctc.201802032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Elwira Bisz
- Department of Chemistry; Opole University; 48 Oleska Street Opole 45-052 Poland
| | | | - Michal Szostak
- Department of Chemistry; Opole University; 48 Oleska Street Opole 45-052 Poland
- Department of Chemistry; Rutgers University; 73 Warren Street Newark NJ 07102 USA
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18
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Abstract
An operationally-simple protocol for the selective C(sp2)–C(sp3) iron-catalyzed cross-coupling of aryl chlorides with Grignard reagents at low catalyst loading is reported.
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Affiliation(s)
- Elwira Bisz
- Department of Chemistry
- Opole University
- 45-052 Opole
- Poland
| | | | | | - Michal Szostak
- Department of Chemistry
- Opole University
- 45-052 Opole
- Poland
- Department of Chemistry
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19
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Bisz E, Szostak M. Iron-Catalyzed C(sp2)–C(sp3) Cross-Coupling of Chlorobenzenesulfonamides with Alkyl Grignard Reagents: Entry to Alkylated Aromatics. J Org Chem 2018; 84:1640-1646. [DOI: 10.1021/acs.joc.8b02886] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Michal Szostak
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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20
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Bisz E, Szostak M. Iron‐Catalyzed C(
sp
2
)−C(
sp
3
) Cross‐Coupling of Chlorobenzamides with Alkyl Grignard Reagents: Development of Catalyst System, Synthetic Scope, and Application. Adv Synth Catal 2018. [DOI: 10.1002/adsc.201800849] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Elwira Bisz
- Department of Chemistry Opole University 48 Oleska Street Opole 45-052 Poland
| | - Michal Szostak
- Department of Chemistry Opole University 48 Oleska Street Opole 45-052 Poland
- Department of Chemistry Rutgers University 73 Warren Street Newark NJ 07102 United States
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21
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Piontek A, Bisz E, Dziuk B, Szostak R, Szostak M. Structures and energetic properties of 4-halobenzamides. Acta Crystallogr C Struct Chem 2018; 74:1395-1402. [PMID: 30398194 DOI: 10.1107/s2053229618013463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Accepted: 09/20/2018] [Indexed: 01/17/2023]
Abstract
The amide bond represents one of the most fundamental functional groups in chemistry. The properties of amides are defined by amidic resonance (nN→π*C=O conjugation), which enforces planarity of the six atoms comprising the amide bond. Despite the importance of 4-halo-substituted benzamides in organic synthesis, molecular interactions and medicinal chemistry, the effect of 4-halo-substitution on the properties of the amide bond in N,N-disubstituted benzamides has not been studied. Herein, we report the crystal structures and energetic properties of a full series of 4-halobenzamides. The structures of four 4-halobenzamides (halo = iodo, bromo, chloro and fluoro) in the N-morpholinyl series have been determined, namely 4-[(4-halophenyl)carbonyl]morpholine, C11H12XNO2, for halo = iodo (X = I), bromo (X = Br), chloro (X = Cl) and fluoro (X = F). Computations have been used to determine the effect of halogen substitution on the structures and resonance energies. 4-Iodo-N-morpholinylbenzamide crystallized with a significant distortion of the amide bond (τ + χN = 33°). The present study supports the correlation between the Ar-C(O) axis twist angle and the twist angle of the amide N-C(O) bond. Comparison of resonance energies in synthetically valuable N-morpholinyl and N-piperidinyl amides demonstrates that the O atom of the morpholinyl ring has a negligible effect on amidic resonance in the series.
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Affiliation(s)
- Aleksandra Piontek
- Department of Chemistry, University of Opole, 48 Oleska Street, Opole 45-052, Poland
| | - Elwira Bisz
- Department of Chemistry, University of Opole, 48 Oleska Street, Opole 45-052, Poland
| | - Błażej Dziuk
- Department of Chemistry, University of Opole, 48 Oleska Street, Opole 45-052, Poland
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA
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22
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Piontek A, Bisz E, Szostak M. Iron-Catalyzed Cross-Couplings in the Synthesis of Pharmaceuticals: In Pursuit of Sustainability. Angew Chem Int Ed Engl 2018; 57:11116-11128. [PMID: 29460380 DOI: 10.1002/anie.201800364] [Citation(s) in RCA: 159] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Indexed: 01/29/2023]
Abstract
The scarcity of precious metals has led to the development of sustainable strategies for metal-catalyzed cross-coupling reactions. The establishment of new catalytic methods using iron is attractive owing to the low cost, abundance, ready availability, and very low toxicity of iron. In the last few years, sustainable methods for iron-catalyzed cross-couplings have entered the critical area of pharmaceutical research. Most notably, iron is one of the very few metals that have been successfully field-tested as highly effective base-metal catalysts in practical, kilogram-scale industrial cross-couplings. In this Minireview, we critically discuss the strategic benefits of using iron catalysts as green and sustainable alternatives to precious metals in cross-coupling applications for the synthesis of pharmaceuticals. The Minireview provides an essential introduction to the fundamental aspects of practical iron catalysis, highlights areas for improvement, and identifies new fields to be explored.
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Affiliation(s)
- Aleksandra Piontek
- Department of Chemistry, Opole University, 48 Oleska Street, 45-052, Opole, Poland
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, 45-052, Opole, Poland
| | - Michal Szostak
- Department of Chemistry, Opole University, 48 Oleska Street, 45-052, Opole, Poland.,Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ, 07102, USA
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23
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Affiliation(s)
- Aleksandra Piontek
- Department of Chemistry Opole University 48 Oleska Street 45-052 Opole Polen
| | - Elwira Bisz
- Department of Chemistry Opole University 48 Oleska Street 45-052 Opole Polen
| | - Michal Szostak
- Department of Chemistry Opole University 48 Oleska Street 45-052 Opole Polen
- Department of Chemistry Rutgers University 73 Warren Street Newark NJ 07102 USA
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24
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Białek M, Bisz E. Dichlorovanadium(IV) diamine-bis(phenolate) complexes for ethylene (co)polymerization and 1-olefin isospecific polymerization. J Catal 2018. [DOI: 10.1016/j.jcat.2018.03.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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25
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Bisz E, Szostak M. 2-Methyltetrahydrofuran: A Green Solvent for Iron-Catalyzed Cross-Coupling Reactions. ChemSusChem 2018; 11:1290-1294. [PMID: 29493907 DOI: 10.1002/cssc.201800142] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Indexed: 05/22/2023]
Abstract
Iron-catalyzed cross-coupling reactions allow sustainable formation of C-C bonds using cost-effective, earth-abundant base-metal catalysis for complex syntheses of pharmaceuticals, natural products, and fine chemicals. The major challenge to maintain full sustainability of the process is the identification of green and renewable solvents that can be harnessed to replace the conventional solvents for this highly attractive reaction. Herein, iron-catalyzed cross-coupling of aryl chlorides and tosylates with challenging organometallic reagents possessing β-hydrogens is found to proceed in good to excellent yields with the green, sustainable, and eco-friendly 2-methyltetrahydrofuran (2-MeTHF) as solvent. The reaction operates with excellent functional group tolerance under very mild conditions. Furthermore, large-scale cross-coupling, cross-coupling of heteroaromatic substrates, and cross-coupling of challenging aryl tosylates and carbamates mediated by Fe-N-heterocyclic carbene catalytic systems in eco-friendly 2-MeTHF were also carried out. The developed method was applied to the key cross-coupling in the synthesis of a fibrinolysis inhibitor, further highlighting the potential of 2-MeTHF as a general solvent for sustainable iron-catalyzed cross-coupling reactions.
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Affiliation(s)
- Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, 45-052, Opole, Poland
| | - Michal Szostak
- Department of Chemistry, Opole University, 48 Oleska Street, 45-052, Opole, Poland
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ, 07102, United States
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26
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Bisz E, Piontek A, Dziuk B, Szostak R, Szostak M. Barriers to Rotation in ortho-Substituted Tertiary Aromatic Amides: Effect of Chloro-Substitution on Resonance and Distortion. J Org Chem 2018; 83:3159-3163. [DOI: 10.1021/acs.joc.8b00019] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Aleksandara Piontek
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Błażej Dziuk
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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27
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Abstract
Oxygen-based electrophiles have emerged as some of the most valuable cross-coupling partners in organic synthesis due to several major strategic and environmental benefits, such as abundance and potential to avoid toxic halide waste. In this context, iron-catalyzed C-O activation/cross-coupling holds particular promise to achieve sustainable catalytic protocols due to its natural abundance, inherent low toxicity, and excellent economic and ecological profile. Recently, tremendous progress has been achieved in the development of new methods for functional-group-tolerant iron-catalyzed cross-coupling reactions by selective C-O cleavage. These methods establish highly attractive alternatives to traditional cross-coupling reactions by using halides as electrophilic partners. In particular, new easily accessible oxygen-based electrophiles have emerged as substrates in iron-catalyzed cross-coupling reactions, which significantly broaden the scope of this catalysis platform. New mechanistic manifolds involving iron catalysis have been established; thus opening up vistas for the development of a wide range of unprecedented reactions. The synthetic potential of this sustainable mode of reactivity has been highlighted by the development of new strategies in the construction of complex motifs, including in target synthesis. The most recent advances in sustainable iron-catalyzed cross-coupling of C-O-based electrophiles are reviewed, with a focus on both mechanistic aspects and synthetic utility. It should be noted that this catalytic manifold provides access to motifs that are often not easily available by other methods, such as the assembly of stereodefined dienes or C(sp2 )-C(sp3 ) cross-couplings, thus emphasizing the synthetic importance of this mode of reactivity.
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Affiliation(s)
- Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, 45-052, Opole, Poland
| | - Michal Szostak
- Department of Chemistry, Opole University, 48 Oleska Street, 45-052, Opole, Poland
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ, 07102, USA
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28
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Spaleniak GP, Bisz E, Białek M, Zarychta B. 2,4-Di-tert-butyl-6-({[2-(di-methyl-amino)-eth-yl](2-hy-droxy-benz-yl)amino}-meth-yl)phenol. Acta Crystallogr Sect E Struct Rep Online 2014; 70:o678. [PMID: 24940258 PMCID: PMC4051019 DOI: 10.1107/s1600536814010241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Accepted: 05/06/2014] [Indexed: 11/10/2022]
Abstract
The title compound, C26H40N2O2, has both its N atoms in trigonal-pyramidal geometries. The molecular structure is stabilized by O—H⋯N and C—H⋯O hydrogen bonds. In the crystal, C—H⋯π interactions lead to the formation of a supramolecular helical chain along the b-axis direction.
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Affiliation(s)
| | - Elwira Bisz
- Faculty of Chemistry, University of Opole, Oleska 48, 45-052 Opole, Poland
| | - Marzena Białek
- Faculty of Chemistry, University of Opole, Oleska 48, 45-052 Opole, Poland
| | - Bartosz Zarychta
- Faculty of Chemistry, University of Opole, Oleska 48, 45-052 Opole, Poland
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29
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Białek M, Bisz E. A comparative study on the polymerization of 1-octene promoted by vanadium and titanium complexes supported by phenoxyimine and salen type ligands. J Polym Res 2013. [DOI: 10.1007/s10965-013-0164-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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