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Shirisha T, Majhi S, Balasubramanian S, Kashinath D. Metal-free C(sp 3)-H functionalization (C-C and C-N bond formation) of 1,2,3,4-tetrahydroacridines using deep eutectic solvents as catalyst and reaction medium. Org Biomol Chem 2024; 22:1434-1440. [PMID: 38265125 DOI: 10.1039/d3ob01752d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
Herein, we report a metal-free and efficient method for the C(sp3)-H functionalization of 1,2,3,4-tetrahydroacridines at the C4-position by the addition of azodicarboxylates (C-N bond) and maleimides (C-C bond) using deep eutectic solvents (DESs) at 80 °C. The C4-functionalized 1,2,3,4-tetrahydroacridines were achieved with high atom efficiency, precise regioselectivity, and yields ranging from 70-96%. The practicality of the developed method has been demonstrated through gram-scale synthesis. Also the green-metrics were calculated for the developed method and it was found that the metrics are near to the ideal values.
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Affiliation(s)
| | - Subir Majhi
- Department of Chemistry, National Institute of Technology, Warangal-506 004, India.
| | - Sridhar Balasubramanian
- Centre for X-ray Crystallography, Department of Analytical & Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Tarnaka, Uppal Road, Hyderabad-500007, Telangana, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201 002, India
| | - Dhurke Kashinath
- Department of Chemistry, National Institute of Technology, Warangal-506 004, India.
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2
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Tan HR, Zhou X, Gong T, You H, Zheng Q, Zhao SY, Xuan W. Anderson-type polyoxometalate-based metal-organic framework as an efficient heterogeneous catalyst for selective oxidation of benzylic C-H bonds. RSC Adv 2024; 14:364-372. [PMID: 38173623 PMCID: PMC10759227 DOI: 10.1039/d3ra07120k] [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: 10/19/2023] [Accepted: 12/11/2023] [Indexed: 01/05/2024] Open
Abstract
Oxidative transformation of benzylic C-H bonds into functional carbonyl groups under mild conditions represents an efficient method for the synthesis of aromatic carboxylic acids and ketones. Here we report a high-efficiency catalyst system constructed from an Anderson-type polyoxometalate-based metal-Organic framework (POMOF-1) and N-hydroxyphthalimide (NHPI) for selective oxidation of methylarenes and alkylarenes under 1 atm O2 atmosphere. POMOF-1 exerted a synergistic effect originating from the well-aligned Anderson {CrMo6} clusters and Cu centers within the framework, and this entailed good cooperation with NHPI to catalyze the selective oxidation. Accordingly, the reactions exhibit good tolerance and chemical selectivity for a wide range of substrates bearing diverse substituent groups, and the corresponding carboxylic acids and ketones were harvested in good yields under mild conditions. Mechanism study reveals that POMOF-1 worked synergistically with NPHI to activate the benzylic C-H bonds of substrates, which are sequentially oxidized by oxygen and HOO˙ to give rise to the products. This work may pave a way to design high-efficiency catalysts by integration of polyoxometalate-based materials with NPHI for challenging C-H activation.
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Affiliation(s)
- Hong-Ru Tan
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Donghua University Shanghai 201620 P. R. China
| | - Xiang Zhou
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University Shanghai 201620 P. R. China
| | - Tengfei Gong
- Jiaxing Jiayuan Inspection Technology Service Co., Ltd Building 2, No. 1403, Hongbo Road, Economic and Technological Development Zone Jiaxing City Zhejiang Province P. R. China
| | - Hanqi You
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Donghua University Shanghai 201620 P. R. China
| | - Qi Zheng
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University Shanghai 201620 P. R. China
| | - Sheng-Yin Zhao
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Donghua University Shanghai 201620 P. R. China
| | - Weimin Xuan
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Donghua University Shanghai 201620 P. R. China
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Dong J, Wu S, Geng F, Yan Y, Liu L, Zhou Y. Selective Oxidative Methyl C-H Functionalization of Butylated Hydroxytoluene toward Arylimines/ N-Heterocycles. J Org Chem 2023; 88:14649-14658. [PMID: 37816698 DOI: 10.1021/acs.joc.3c01643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/12/2023]
Abstract
A metal-free and selective oxidative methyl C-H functionalization of BHT with aniline compounds has been developed. This innovative method enables the facile and efficient synthesis of a diverse array of BHT-functionalized N-containing skeletons, including arylamines, benzoxazoles, benzothiazoles, benzimidazoles, quinazolines, and quinazolinones, all of which are challenging to access. The control experiment involving TEMP18O suggests that the radical adduct of TEMPO with the benzyl radical of BHT may serve as an intermediate.
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Affiliation(s)
- Jianyu Dong
- School of Physics and Chemistry, Hunan First Normal University, Changsha 410205, China
| | - Shaofeng Wu
- School of Physics and Chemistry, Hunan First Normal University, Changsha 410205, China
- State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, Key Laboratory of Oil and Gas Fine Chemicals, Ministry of Education & Xinjiang Uygur Autonomous Region, Urumqi Key Laboratory of Green Catalysis and Synthesis Technology, College of Chemistry, Xinjiang University, Urumqi 830017, China
| | - Furong Geng
- School of Physics and Chemistry, Hunan First Normal University, Changsha 410205, China
- Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Yani Yan
- Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Long Liu
- School of Physics and Chemistry, Hunan First Normal University, Changsha 410205, China
- Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Yongbo Zhou
- Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
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Abstract
Nitroxides, also known as nitroxyl radicals, are long-lived or stable radicals with the general structure R1R2N-O•. The spin distribution over the nitroxide N and O atoms contributes to the thermodynamic stability of these radicals. The presence of bulky N-substituents R1 and R2 prevents nitroxide radical dimerization, ensuring their kinetic stability. Despite their reactivity toward various transient C radicals, some nitroxides can be easily stored under air at room temperature. Furthermore, nitroxides can be oxidized to oxoammonium salts (R1R2N═O+) or reduced to anions (R1R2N-O-), enabling them to act as valuable oxidants or reductants depending on their oxidation state. Therefore, they exhibit interesting reactivity across all three oxidation states. Due to these fascinating properties, nitroxides find extensive applications in diverse fields such as biochemistry, medicinal chemistry, materials science, and organic synthesis. This review focuses on the versatile applications of nitroxides in organic synthesis. For their use in other important fields, we will refer to several review articles. The introductory part provides a brief overview of the history of nitroxide chemistry. Subsequently, the key methods for preparing nitroxides are discussed, followed by an examination of their structural diversity and physical properties. The main portion of this review is dedicated to oxidation reactions, wherein parent nitroxides or their corresponding oxoammonium salts serve as active species. It will be demonstrated that various functional groups (such as alcohols, amines, enolates, and alkanes among others) can be efficiently oxidized. These oxidations can be carried out using nitroxides as catalysts in combination with various stoichiometric terminal oxidants. By reducing nitroxides to their corresponding anions, they become effective reducing reagents with intriguing applications in organic synthesis. Nitroxides possess the ability to selectively react with transient radicals, making them useful for terminating radical cascade reactions by forming alkoxyamines. Depending on their structure, alkoxyamines exhibit weak C-O bonds, allowing for the thermal generation of C radicals through reversible C-O bond cleavage. Such thermally generated C radicals can participate in various radical transformations, as discussed toward the end of this review. Furthermore, the application of this strategy in natural product synthesis will be presented.
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Affiliation(s)
- Dirk Leifert
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Armido Studer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
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Wang Y, Zhao L, Liu S, Ji G, He C, Tang Y, Duan C. Mixed-Component Metal-Organic Framework for Boosting Synergistic Photoactivation of C(sp 3)-H and Oxygen. ACS APPLIED MATERIALS & INTERFACES 2023; 15:16744-16754. [PMID: 36943723 DOI: 10.1021/acsami.2c23245] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Synergistic catalysis is an efficient and powerful strategy for simultaneously activating reactants by multiple active sites to promote the efficiency of difficult and challenging catalytic reactions. Meanwhile, enzymes with multi-active-site synergistic catalytic properties possessing high efficiency and high selectivity have become the goal pursued in the field of catalytic chemistry in recent years. Metal-organic frameworks (MOFs), as an effective heterogeneous catalytic platform, that can integrate multiple active sites for synergistic catalysis like enzymatic systems have recently attracted interest. Herein, we report a doubly interpenetrated metal-organic framework with dual active sites, MnIII-porphyrin sites to directly activate molecular oxygen and fluoren-9-one sites to produce a hydrogen atom transfer (HAT) agent by the proton-coupled electron transfer (PCET) process to simultaneously activate inert C(sp3)-H bonds for efficient inert C(sp3)-H bond oxidation under mild conditions. The bifunctional mixed-component MOF structure forced the two catalytic sites closer together to a more suitable distance, exhibiting high photocatalytic activity for inert C(sp3)-H bond oxidation with almost unique selectivity under mild conditions. The density functional theory (DFT) calculation of free energy during the whole catalytic process demonstrated that it is likely that the synergistic catalytic process occurred in the interframework to accelerate the catalytic reaction. The assembling mixed-component MOF for synergistic catalysis would be a prospective approach for the inert C(sp3)-H photoactivation and functionalization.
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Affiliation(s)
- Yefei Wang
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, Dalian University of Technology, Dalian 116024, P. R. China
| | - Liang Zhao
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, Dalian University of Technology, Dalian 116024, P. R. China
| | - Songtao Liu
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, Dalian University of Technology, Dalian 116024, P. R. China
| | - Guanfeng Ji
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, Dalian University of Technology, Dalian 116024, P. R. China
| | - Cheng He
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, Dalian University of Technology, Dalian 116024, P. R. China
| | - Yang Tang
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, Dalian University of Technology, Dalian 116024, P. R. China
| | - Chunying Duan
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, Dalian University of Technology, Dalian 116024, P. R. China
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Huang H, Jing X, Deng J, Meng C, Duan C. Enzyme-Inspired Coordination Polymers for Selective Oxidization of C(sp 3)-H Bonds via Multiphoton Excitation. J Am Chem Soc 2023; 145:2170-2182. [PMID: 36657380 DOI: 10.1021/jacs.2c09348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Nature's blueprint provides the fundamental principles for expanding the use of abundant metals in catalysis; however, mimicking both the structure and function of copper enzymes simultaneously in one artificial system for selective C-H bond oxidation faces marked challenges. Herein, we report a new approach to the assembly of artificial monooxygenases utilizing a binuclear Cu2S2Cl2 cluster to duplicate the identical structure and catalysis of the CuA enzyme. The designed monooxygenase Cu-Cl-bpyc facilitates well-defined redox potential that initially activated O2via photoinduced electron transfer, and generated an active chlorine radical via a ligand-to-metal charge transfer (LMCT) process from the consecutive excitation of the in situ formed copper(II) center. The chlorine radical abstracts a hydrogen atom selectively from C(sp3)-H bonds to generate the radical intermediate; meanwhile, the O2•- species interacted with the mimic to form mixed-valence species, giving the desired oxidization products with inherent product selectivity of copper monooxygenases and recovering the catalyst directly. This enzymatic protocol exhibits excellent recyclability, good functional group tolerance, and broad substrate scope, including some biological and pharmacologically relevant targets. Mechanistic studies indicate that the C-H bond cleavage was the rate-determining step and the cuprous interactions were essential to stabilize the active oxygen species. The well-defined structural characters and the fine-modified catalytic properties open a new avenue to develop robust artificial enzymes with uniform and precise active sites and high catalytic performances.
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Affiliation(s)
- Huilin Huang
- State Key Laboratory of Fine Chemicals, Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian116024, China
| | - Xu Jing
- State Key Laboratory of Fine Chemicals, Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian116024, China
| | - Jiangtao Deng
- State Key Laboratory of Fine Chemicals, Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian116024, China
| | - Changgong Meng
- State Key Laboratory of Fine Chemicals, Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian116024, China
| | - Chunying Duan
- State Key Laboratory of Fine Chemicals, Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian116024, China
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7
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Liu XH, Yu HY, Huang JY, Zhou XT, Xue C, Ji HB. Time-resolved EPR revealed C(sp 3)–H activation through a photo-enhanced phthalimide- N-oxyl (PINO) radical. Chem Commun (Camb) 2023; 59:243-246. [DOI: 10.1039/d2cc05906a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The time-resolved EPR technique under operando photochemical conditions as an efficient strategy to investigate the fast formation of abundant long-lived PINO radicals and their activation of the C(sp3)–H reaction is reported.
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Affiliation(s)
- Xiao-Hui Liu
- Fine Chemical Industry Research Institute, School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai, 519082, China
| | - Hai-Yang Yu
- Fine Chemical Industry Research Institute, School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai, 519082, China
| | - Jia-Ying Huang
- Fine Chemical Industry Research Institute, School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai, 519082, China
| | - Xian-Tai Zhou
- Fine Chemical Industry Research Institute, School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai, 519082, China
| | - Can Xue
- Fine Chemical Industry Research Institute, School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai, 519082, China
| | - Hong-Bing Ji
- Fine Chemical Industry Research Institute, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China
- Advanced Energy Science and Technology Guangdong Laboratory, Huizhou, Guangdong, 516003, China
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8
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Lopat’eva ER, Krylov IB, Lapshin DA, Terent’ev AO. Redox-active molecules as organocatalysts for selective oxidative transformations - an unperceived organocatalysis field. Beilstein J Org Chem 2022; 18:1672-1695. [PMID: 36570566 PMCID: PMC9749543 DOI: 10.3762/bjoc.18.179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 11/23/2022] [Indexed: 12/13/2022] Open
Abstract
Organocatalysis is widely recognized as a key synthetic methodology in organic chemistry. It allows chemists to avoid the use of precious and (or) toxic metals by taking advantage of the catalytic activity of small and synthetically available molecules. Today, the term organocatalysis is mainly associated with redox-neutral asymmetric catalysis of C-C bond-forming processes, such as aldol reactions, Michael reactions, cycloaddition reactions, etc. Organophotoredox catalysis has emerged recently as another important catalysis type which has gained much attention and has been quite well-reviewed. At the same time, there are a significant number of other processes, especially oxidative, catalyzed by redox-active organic molecules in the ground state (without light excitation). Unfortunately, many of such processes are not associated in the literature with the organocatalysis field and thus many achievements are not fully consolidated and systematized. The present article is aimed at overviewing the current state-of-art and perspectives of oxidative organocatalysis by redox-active molecules with the emphasis on challenging chemo-, regio- and stereoselective CH-functionalization processes. The catalytic systems based on N-oxyl radicals, amines, thiols, oxaziridines, ketone/peroxide, quinones, and iodine(I/III) compounds are the most developed catalyst types which are covered here.
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Affiliation(s)
- Elena R Lopat’eva
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospect 47, Moscow, 119991, Russia
| | - Igor B Krylov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospect 47, Moscow, 119991, Russia
| | - Dmitry A Lapshin
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospect 47, Moscow, 119991, Russia
| | - Alexander O Terent’ev
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospect 47, Moscow, 119991, Russia
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Liu XH, Yu HY, Huang JY, Su JH, Xue C, Zhou XT, He YR, He Q, Xu DJ, Xiong C, Ji HB. Biomimetic catalytic aerobic oxidation of C-sp(3)-H bonds under mild conditions using galactose oxidase model compound Cu IIL. Chem Sci 2022; 13:9560-9568. [PMID: 36091900 PMCID: PMC9400635 DOI: 10.1039/d2sc02606f] [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: 05/10/2022] [Accepted: 07/28/2022] [Indexed: 11/21/2022] Open
Abstract
Developing highly efficient catalytic protocols for C-sp(3)-H bond aerobic oxidation under mild conditions is a long-desired goal of chemists. Inspired by nature, a biomimetic approach for the aerobic oxidation of C-sp(3)-H by galactose oxidase model compound CuIIL and NHPI (N-hydroxyphthalimide) was developed. The CuIIL-NHPI system exhibited excellent performance in the oxidation of C-sp(3)-H bonds to ketones, especially for light alkanes. The biomimetic catalytic protocol had a broad substrate scope. Mechanistic studies revealed that the CuI-radical intermediate species generated from the intramolecular redox process of CuIILH2 was critical for O2 activation. Kinetic experiments showed that the activation of NHPI was the rate-determining step. Furthermore, activation of NHPI in the CuIIL-NHPI system was demonstrated by time-resolved EPR results. The persistent PINO (phthalimide-N-oxyl) radical mechanism for the aerobic oxidation of C-sp(3)-H bond was demonstrated.
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Affiliation(s)
- Xiao-Hui Liu
- Fine Chemical Industry Research Institute, School of Chemical Engineering and Technology, Sun Yat-sen University Zhuhai 519082 China
| | - Hai-Yang Yu
- Fine Chemical Industry Research Institute, School of Chemical Engineering and Technology, Sun Yat-sen University Zhuhai 519082 China
| | - Jia-Ying Huang
- Fine Chemical Industry Research Institute, School of Chemical Engineering and Technology, Sun Yat-sen University Zhuhai 519082 China
| | - Ji-Hu Su
- CAS Key Laboratory of Microscale Magnetic Resonance, University of Science and Technology of China Hefei 230026 China
| | - Can Xue
- Fine Chemical Industry Research Institute, School of Chemical Engineering and Technology, Sun Yat-sen University Zhuhai 519082 China
| | - Xian-Tai Zhou
- Fine Chemical Industry Research Institute, School of Chemical Engineering and Technology, Sun Yat-sen University Zhuhai 519082 China
| | - Yao-Rong He
- Fine Chemical Industry Research Institute, School of Chemistry, Sun Yat-sen University Guangzhou 510275 China
| | - Qian He
- Fine Chemical Industry Research Institute, School of Chemistry, Sun Yat-sen University Guangzhou 510275 China
| | - De-Jing Xu
- Fine Chemical Industry Research Institute, School of Chemical Engineering and Technology, Sun Yat-sen University Zhuhai 519082 China
| | - Chao Xiong
- Fine Chemical Industry Research Institute, School of Chemistry, Sun Yat-sen University Guangzhou 510275 China
| | - Hong-Bing Ji
- Fine Chemical Industry Research Institute, School of Chemistry, Sun Yat-sen University Guangzhou 510275 China
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Zhou W, Sarma T, Su Y, Lei C, Sessler JL. Kinetic trapping of a cobalt(ii) metallocage using a carbazole-containing expanded carbaporphyrinoid ligand. Chem Sci 2022; 13:692-697. [PMID: 35173933 PMCID: PMC8768885 DOI: 10.1039/d1sc06514a] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 12/19/2021] [Indexed: 11/21/2022] Open
Abstract
The meso-unsubstituted expanded porphyrinoid 3, incorporating two carbazole moieties, acts as an effective ligand for Co(ii) and permits the isolation and X-ray diffraction-based characterization of a 6 : 3 metal-to-ligand metallocage complex that converts spontaneously to the constituent 2 : 1 metal-to-ligand metalloring species in chloroform solution. The discrete metalloring is formed directly when the Co(ii) complex is crystallized from supersaturated solutions, whereas crystallization from more dilute solutions favors the metallocage. Studies with two other test cations, Pd(ii) and Zn(ii), revealed exclusive formation of the monomeric metalloring complexes with no evidence of higher order species being formed. Structural, electrochemical and UV-vis-NIR absorption spectral studies provide support for the conclusion that the Pd(ii) complex is less distorted and more effectively conjugated than its Co(ii) and Zn(ii) congeners, an inference further supported by TD-DFT calculations. The findings reported here underscore how expanded porphyrins can support coordination modes, including bimetallic complexes and self-assembled cage structures, that are not necessarily easy to access using more traditional ligand systems. Carbazole containing expanded carbaporphyrinoid ligand supports the formation of 2 : 1 metal-to-ligand complexes with Pd, Co, and Zn. Solid-state studies also revealed formation of a 6 : 3 metal-to-ligand metallocage in the case of Co complexation.![]()
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Affiliation(s)
- Weinan Zhou
- School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China
- Center for Supramolecular Chemistry and Catalysis and Department of Chemistry, College of Science, Shanghai University, Shanghai 200444, China
| | - Tridib Sarma
- Department of Chemistry, Cotton University, Guwahati 781001, Assam, India
| | - Yonghuan Su
- Center for Supramolecular Chemistry and Catalysis and Department of Chemistry, College of Science, Shanghai University, Shanghai 200444, China
| | - Chuanhu Lei
- Center for Supramolecular Chemistry and Catalysis and Department of Chemistry, College of Science, Shanghai University, Shanghai 200444, China
| | - Jonathan L. Sessler
- Department of Chemistry, The University of Texas at Austin, 105 East 24th Street, Stop A5300, Austin, Texas 78712-1224, USA
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