1
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Hölter N, Rendel NH, Spierling L, Kwiatkowski A, Kleinmans R, Daniliuc CG, Wenger OS, Glorius F. Phenothiazine Sulfoxides as Active Photocatalysts for the Synthesis of γ-Lactones. J Am Chem Soc 2025; 147:12908-12916. [PMID: 40174889 PMCID: PMC12007001 DOI: 10.1021/jacs.5c01988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2025] [Revised: 03/12/2025] [Accepted: 03/14/2025] [Indexed: 04/04/2025]
Abstract
N-substituted phenothiazines are prominent and highly effective organic photoredox catalysts, particularly known for their strong reducing capabilities. Despite their wide utility, the closely related phenothiazine sulfoxides, which easily form upon oxidation, have been largely overlooked and have not been explored in the context of photocatalysis. Herein, we describe the discovery and application of N-phenylphenothiazine sulfoxide as a photocatalyst for the reductive activation of cyclic malonyl peroxides, giving access to complex γ-lactones starting from simple olefins. Detailed mechanistic studies were carried out to better understand the in situ formation of the active catalyst species from a commercial precursor, as well as the catalyst species interconversion and the photocatalytic mechanism for the formation of γ-lactone products. Specifically, we employed a broad range of mechanistic tools, including time-resolved spectroscopy, spectroelectrochemistry, transient UV-vis absorption spectroscopy, cyclic voltammetry, isotopic labeling, radical trapping experiments, NMR spectroscopy, and density functional theory (DFT) calculations. The synthetic utility of this protocol is demonstrated in a substrate scope study, highlighting the facile access to complex spirocyclic γ-lactones, which are widely recognized for their biological importance.
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Affiliation(s)
- Niklas Hölter
- Organisch-Chemisches
Institut, University of Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Nils H. Rendel
- Organisch-Chemisches
Institut, University of Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Leander Spierling
- Department
of Chemistry, University of Basel, St. Johanns-Ring 19, CH-4056 Basel, Switzerland
| | - Adrian Kwiatkowski
- Organisch-Chemisches
Institut, University of Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Roman Kleinmans
- Organisch-Chemisches
Institut, University of Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches
Institut, University of Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Oliver S. Wenger
- Department
of Chemistry, University of Basel, St. Johanns-Ring 19, CH-4056 Basel, Switzerland
| | - Frank Glorius
- Organisch-Chemisches
Institut, University of Münster, Corrensstraße 36, 48149 Münster, Germany
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2
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Song B, Zhang Y, Liu Z, Boulay P, Dietlin C, Morlet-Savary F, Schmitt M, Gigmes D, Becht JM, Dumur F, Lalevée J. Photoredox Catalysts Based on N-(Hexyl)benzothioxanthene-3,4-dicarboximide for Photopolymerization and 3D Printing Under Visible Light. Angew Chem Int Ed Engl 2025:e202501442. [PMID: 40227856 DOI: 10.1002/anie.202501442] [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] [Received: 01/17/2025] [Revised: 04/11/2025] [Accepted: 04/14/2025] [Indexed: 04/16/2025]
Abstract
Photoredox catalytic systems are widely used in free radical polymerization as an important photoinitiating approach. However, many reported photoredox catalytic systems are limited by their low stabilities, high excitation powers, and low initiating efficiencies upon excitation in the visible region. Therefore, it is still a great challenge to develop efficient photoinitiating systems for photopolymerization under visible light. In this work, three new effective photosensitizers from N-(hexyl)benzothioxanthene-3,4-dicarboximide derivatives, namely 2-hexyl-1H-thioxantheno[2,1,9-def]isoquinoline-1,3(2H)-dione (BTXI), 5-bromo-2-hexyl-1H-thioxantheno[2,1,9-def]isoquinoline-1,3(2H)-dione (BTXI-Br) and 2-hexyl-1H-thioxantheno[2,1,9-def]isoquinoline-1,3(2H)-dione 6,6-dioxide (BTXIO), were designed by density functional theory calculation and synthesized as photoredox catalysts for visible light induced photopolymerization. When combined with initiators such as oxidants, that is, bis(4-tert-butylphenyl)iodonium hexafluorophosphate or sulfonium salts (i.e., thianthrenium salts, phenoxathiinium salt, phenothiazinium salt, dibenzothiophenium salt) and the reductant ethyl dimethylaminobenzoate to form three-component initiating systems, they showed good to high performance in visible light photo polymerizations with LED@405 nm and LED@450 nm. In addition, these photoinitiating systems enable the successful digital light processing and direct laser writing of 3D structures with high resolution, demonstrating a promising strategy for 3D printing applications.
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Affiliation(s)
- Bin Song
- Université de Haute Alsace, CNRS, IS2M, UMR 7361, Mulhouse, F-68100, France
- Université de Strasbourg, Strasbourg, France
| | - Yijun Zhang
- Université de Haute Alsace, CNRS, IS2M, UMR 7361, Mulhouse, F-68100, France
- Université de Strasbourg, Strasbourg, France
| | - Zheng Liu
- Aix Marseille Univ, CNRS, ICR, UMR 7273, Marseilles, F-13397, France
| | - Pierre Boulay
- Université de Haute Alsace, CNRS, IS2M, UMR 7361, Mulhouse, F-68100, France
- Université de Strasbourg, Strasbourg, France
| | - Céline Dietlin
- Université de Haute Alsace, CNRS, IS2M, UMR 7361, Mulhouse, F-68100, France
- Université de Strasbourg, Strasbourg, France
| | - Fabrice Morlet-Savary
- Université de Haute Alsace, CNRS, IS2M, UMR 7361, Mulhouse, F-68100, France
- Université de Strasbourg, Strasbourg, France
| | - Michael Schmitt
- Université de Haute Alsace, CNRS, IS2M, UMR 7361, Mulhouse, F-68100, France
- Université de Strasbourg, Strasbourg, France
| | - Didier Gigmes
- Aix Marseille Univ, CNRS, ICR, UMR 7273, Marseilles, F-13397, France
| | - Jean-Michel Becht
- Université de Haute Alsace, CNRS, IS2M, UMR 7361, Mulhouse, F-68100, France
- Université de Strasbourg, Strasbourg, France
| | - Frédéric Dumur
- Aix Marseille Univ, CNRS, ICR, UMR 7273, Marseilles, F-13397, France
| | - Jacques Lalevée
- Université de Haute Alsace, CNRS, IS2M, UMR 7361, Mulhouse, F-68100, France
- Université de Strasbourg, Strasbourg, France
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3
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Yang Q, Wen MM, Ruan YJ, Wang XL, Zhang CZ, Wang PF, Hu XY, Xiao YH, Liu XG. Stereoretentive Conversion to C-Glycosides from S-Glycosides via Ligand-Coupling on Sulfur(IV). Org Lett 2025; 27:954-960. [PMID: 39836883 DOI: 10.1021/acs.orglett.4c04338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2025]
Abstract
A novel strategy is reported for the stereoselective synthesis of C(sp2)-C(sp3) C-glycosides, which converts heteroaryl S-glycosides into heteroaryl C-glycosides with retention of configuration through a sequential process involving oxidation and Grignard reagent attack. The new method involves the generation of a S(IV) intermediate, followed by ligand coupling of the glycosyl and heteroaryl groups to yield heteroaryl C-glycosides. The diverse heteroaryl C-glycosides were achieved with good efficiency.
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Affiliation(s)
- Qian Yang
- The Zhongzhou Laboratory for Integrative Biology, State Key Laboratory of Antiviral Drugs, School of Pharmacy, Henan University, Kaifeng, Henan 475004, China
| | - Miao-Miao Wen
- The Zhongzhou Laboratory for Integrative Biology, State Key Laboratory of Antiviral Drugs, School of Pharmacy, Henan University, Kaifeng, Henan 475004, China
| | - Yu-Jun Ruan
- The Zhongzhou Laboratory for Integrative Biology, State Key Laboratory of Antiviral Drugs, School of Pharmacy, Henan University, Kaifeng, Henan 475004, China
| | - Xiao-Li Wang
- The Zhongzhou Laboratory for Integrative Biology, State Key Laboratory of Antiviral Drugs, School of Pharmacy, Henan University, Kaifeng, Henan 475004, China
| | - Cong-Zhen Zhang
- The Zhongzhou Laboratory for Integrative Biology, State Key Laboratory of Antiviral Drugs, School of Pharmacy, Henan University, Kaifeng, Henan 475004, China
| | - Peng-Fei Wang
- The Zhongzhou Laboratory for Integrative Biology, State Key Laboratory of Antiviral Drugs, School of Pharmacy, Henan University, Kaifeng, Henan 475004, China
| | - Xin-Yue Hu
- The Zhongzhou Laboratory for Integrative Biology, State Key Laboratory of Antiviral Drugs, School of Pharmacy, Henan University, Kaifeng, Henan 475004, China
| | - Yu-He Xiao
- The Zhongzhou Laboratory for Integrative Biology, State Key Laboratory of Antiviral Drugs, School of Pharmacy, Henan University, Kaifeng, Henan 475004, China
| | - Xu-Ge Liu
- The Zhongzhou Laboratory for Integrative Biology, State Key Laboratory of Antiviral Drugs, School of Pharmacy, Henan University, Kaifeng, Henan 475004, China
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4
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Zhou M, Tsien J, Dykstra R, Hughes JME, Peters BK, Merchant RR, Gutierrez O, Qin T. Alkyl sulfinates as cross-coupling partners for programmable and stereospecific installation of C(sp 3) bioisosteres. Nat Chem 2023; 15:550-559. [PMID: 36864142 PMCID: PMC10838399 DOI: 10.1038/s41557-023-01150-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 01/30/2023] [Indexed: 03/04/2023]
Abstract
In recent years, a variety of cycloalkyl groups with quaternary carbons, in particular cyclopropyl and cyclobutyl trifluoromethyl groups, have emerged as promising bioisosteres in drug-like molecules. The modular installation of such bioisosteres remains challenging to synthetic chemists. Alkyl sulfinate reagents have been developed as radical precursors to prepare functionalized heterocycles with the desired alkyl bioisosteres. However, the innate (radical) reactivity of this transformation poses reactivity and regioselectivity challenges for the functionalization of any aromatic or heteroaromatic scaffold. Here we showcase the ability of alkyl sulfinates to engage in sulfurane-mediated C(sp3)-C(sp2) cross-coupling, thereby allowing for programmable and stereospecific installation of these alkyl bioisosteres. The ability of this method to simplify retrosynthetic analysis is exemplified by the improved synthesis of multiple medicinally relevant scaffolds. Experimental studies and theoretical calculations for the mechanism of this sulfur chemistry reveal a ligand-coupling trend under alkyl Grignard activation via the sulfurane intermediate, stabilized by solvation of tetrahydrofuran.
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Affiliation(s)
- Min Zhou
- Department of Biochemistry, The University of Texas Southwestern Medical Center, Harry Hines Blvd, Dallas, TX, USA
| | - Jet Tsien
- Department of Biochemistry, The University of Texas Southwestern Medical Center, Harry Hines Blvd, Dallas, TX, USA
| | - Ryan Dykstra
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, USA
| | - Jonathan M E Hughes
- Department of Process Research and Development, Merck & Co., Inc., Rahway, NJ, USA
| | - Byron K Peters
- Department of Process Research and Development, Merck & Co., Inc., Rahway, NJ, USA
| | - Rohan R Merchant
- Department of Discovery Chemistry, Merck & Co., Inc., South San Francisco, CA, USA
| | - Osvaldo Gutierrez
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, USA.
- Department of Chemistry, Texas A&M University, College Station, TX, USA.
| | - Tian Qin
- Department of Biochemistry, The University of Texas Southwestern Medical Center, Harry Hines Blvd, Dallas, TX, USA.
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5
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Yoshida T, Honda Y, Morofuji T, Kano N. Transition-Metal-Free O-Arylation of Alcohols and Phenols with S-Arylphenothiaziniums. J Org Chem 2022; 87:7565-7573. [PMID: 35578794 DOI: 10.1021/acs.joc.2c00771] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Herein, we report the transition-metal-free O-arylation of alcohols and phenols with S-arylphenothiaziniums, which can be easily synthesized from boronic acids. Aryl substituents derived from arylboronic acids were selectively introduced into the hydroxy groups in alcohols and phenols, and a variety of aryl ethers were synthesized. This selectivity is supported by theoretical calculations.
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Affiliation(s)
- Tatsuki Yoshida
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
| | - Yuki Honda
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
| | - Tatsuya Morofuji
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
| | - Naokazu Kano
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
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6
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Tian ZY, Zhang CP. Visible-Light-Initiated Catalyst-Free Trifluoromethylselenolation of Arylsulfonium Salts with [Me4N][SeCF3]. Org Chem Front 2022. [DOI: 10.1039/d2qo00235c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The redox potential gap between arylsulfonium salt and [Me4N][SeCF3] has been clearly disclosed by CV measurements. Construction of carbon-selenium bond by overcoming this gap without using catalysts and additives is...
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