1
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Zhang X, Shen Y, Rovis T. Photoinduced Nickel-Catalyzed Selective N-Demethylation of Trialkylamines Using C(sp 2)-Bromides as HAT Reagents. J Am Chem Soc 2023; 145:3294-3300. [PMID: 36724205 PMCID: PMC9997100 DOI: 10.1021/jacs.2c12767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
N-Demethylation of trialkylamines is a useful transformation, but typically requires harsh reaction conditions and stepwise procedures, as well as judicious protection of labile functional groups. Herein we report a mild, catalytic approach for the demethylation of trialkylamines by utilizing photoinduced nickel catalysis wherein C(sp2)-bromides serve as hydrogen-atom transfer (HAT) reagents. This method achieves direct demethylation of trialkylamines with wide functional group compatibility, making it highly suitable for late-stage derivatization of complex molecules. Mechanistic investigations provide evidence that C(sp2) radicals generated via photoinduced Ni-C(sp2) bond homolysis are involved in hydrogen atom abstraction from trialkylamines. Utilizing steric control of the C(sp2)-bromides, our HAT approach achieves demethylation with excellent site selectivity in the presence of benzyl-substituted amines, which is complementary to the selectivity of classical approaches that afford debenzylation product instead.
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Affiliation(s)
- Xiao Zhang
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Yangyang Shen
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Tomislav Rovis
- Department of Chemistry, Columbia University, New York, New York 10027, United States
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2
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Ziegenbalg D, Pannwitz A, Rau S, Dietzek‐Ivanšić B, Streb C. Comparative Evaluation of Light‐Driven Catalysis: A Framework for Standardized Reporting of Data**. Angew Chem Int Ed Engl 2022; 61:e202114106. [PMID: 35698245 PMCID: PMC9401044 DOI: 10.1002/anie.202114106] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Indexed: 01/05/2023]
Affiliation(s)
- Dirk Ziegenbalg
- Institute of Chemical Engineering Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Andrea Pannwitz
- Institute of Inorganic Chemistry I Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Sven Rau
- Institute of Inorganic Chemistry I Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Benjamin Dietzek‐Ivanšić
- Institute of Physical Chemistry and Center of Energy and Environmental Chemistry Jena (CEEC Jena) Friedrich Schiller University Jena Helmholtzweg 4 07743 Jena Germany
- Department Functional Interfaces Leibniz Institute of Photonic Technology Jena (IPHT) Albert-Einstein-Straße 9 07745 Jena Germany
| | - Carsten Streb
- Institute of Inorganic Chemistry I Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
- Department of Chemistry Johannes Gutenberg University Mainz Duesbergweg 10-14 55128 Mainz Germany
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3
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Nicholas RJ, McGuire MA, Hyun SH, Cullison MN, Thompson DH. Development of an Efficient, High Purity Continuous Flow Synthesis of Diazepam. FRONTIERS IN CHEMICAL ENGINEERING 2022. [DOI: 10.3389/fceng.2022.877498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In an effort to strengthen the resiliency of supply chains for active pharmaceutical ingredients (API), continuous manufacturing processes may be optimized with respect to improved chemoselectivity, production rate, yield, and/or process intensity. We report an efficient two-step continuous flow synthesis of diazepam, an agent on the World Health Organization’s (WHO) list of essential medicines. Different conditions were rapidly screened in microfluidic chip reactors by varying residence times, temperatures, solvents, and ammonia sources to identify the best telescoped reaction conditions. We report a telescoped flow synthesis that uses two microreactors in series set to 0°C and 60°C, respectively, to produce a 96% yield of 91% pure diazepam within 15 min using an NH4Br/NH4OH solution in the second step. Diazepam of >98% purity was obtained after a single recrystallization.
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4
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Ziegenbalg D, Pannwitz A, Rau S, Dietzek‐Ivanšić B, Streb C. Vergleichende Evaluierung lichtgetriebener Katalyse: Ein Rahmenkonzept für das standardisierte Berichten von Daten**. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202114106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Dirk Ziegenbalg
- Institut für Chemieingenieurwesen Universität Ulm Albert-Einstein-Allee 11 89081 Ulm Deutschland
| | - Andrea Pannwitz
- Institut für Anorganische Chemie I Universität Ulm Albert-Einstein-Allee 11 89081 Ulm Deutschland
| | - Sven Rau
- Institut für Anorganische Chemie I Universität Ulm Albert-Einstein-Allee 11 89081 Ulm Deutschland
| | - Benjamin Dietzek‐Ivanšić
- Institut für Physikalische Chemie und Center of Energy and Environmental Chemistry Jena (CEEC Jena) Friedrich-Schiller-Universität Jena Helmholtzweg 4 07743 Jena Deutschland
- Department Funktionale Grenzflächen Leibniz-Institut für Photonische Technologien Jena (IPHT) Albert-Einstein-Straße 9 07745 Jena Deutschland
| | - Carsten Streb
- Institut für Anorganische Chemie I Universität Ulm Albert-Einstein-Allee 11 89081 Ulm Deutschland
- Department of Chemistry Johannes Gutenberg University Mainz Duesbergweg 10-14 55128 Mainz Germany
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5
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Najmi AA, Bischoff R, Permentier HP. N-Dealkylation of Amines. Molecules 2022; 27:molecules27103293. [PMID: 35630770 PMCID: PMC9146227 DOI: 10.3390/molecules27103293] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 05/03/2022] [Accepted: 05/08/2022] [Indexed: 02/01/2023] Open
Abstract
N-dealkylation, the removal of an N-alkyl group from an amine, is an important chemical transformation which provides routes for the synthesis of a wide range of pharmaceuticals, agrochemicals, bulk and fine chemicals. N-dealkylation of amines is also an important in vivo metabolic pathway in the metabolism of xenobiotics. Identification and synthesis of drug metabolites such as N-dealkylated metabolites are necessary throughout all phases of drug development studies. In this review, different approaches for the N-dealkylation of amines including chemical, catalytic, electrochemical, photochemical and enzymatic methods will be discussed.
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6
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Abstract
This paper is the forty-third consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2020 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY, 11367, United States.
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7
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Xin Y, Shen C, Tang M, Guo Z, Shi Y, Gu Z, Shao J, Zhang L. Recreating the natural evolutionary trend in key microdomains provides an effective strategy for engineering of a thermomicrobial N-demethylase. J Biol Chem 2022; 298:101656. [PMID: 35124004 PMCID: PMC8892156 DOI: 10.1016/j.jbc.2022.101656] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/22/2022] [Accepted: 01/24/2022] [Indexed: 01/10/2023] Open
Abstract
N-demethylases have been reported to remove the methyl groups on primary or secondary amines, which could further affect the properties and functions of biomacromolecules or chemical compounds; however, the substrate scope and the robustness of N-demethylases have not been systematically investigated. Here we report the recreation of natural evolution in key microdomains of the Thermomicrobium roseum sarcosine oxidase (TrSOX), an N-demethylase with marked stability (melting temperature over 100 °C) and enantioselectivity, for enhanced substrate scope and catalytic efficiency on -C-N- bonds. We obtained the structure of TrSOX by crystallization and X-ray diffraction (XRD) for the initial framework. The natural evolution in the nonconserved residues of key microdomains—including the catalytic loop, coenzyme pocket, substrate pocket, and entrance site—was then identified using ancestral sequence reconstruction (ASR), and the substitutions that accrued during natural evolution were recreated by site-directed mutagenesis. The single and double substitution variants catalyzed the N-demethylation of N-methyl-L-amino acids up to 1800- and 6000-fold faster than the wild type, respectively. Additionally, these single substitution variants catalyzed the terminal N-demethylation of non-amino-acid compounds and the oxidation of the main chain -C-N- bond to a -C=N- bond in the nitrogen-containing heterocycle. Notably, these variants retained the enantioselectivity and stability of the initial framework. We conclude that the variants of TrSOX are of great potential use in N-methyl enantiomer resolution, main-chain Schiff base synthesis, and alkaloid modification or degradation.
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8
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Buglioni L, Raymenants F, Slattery A, Zondag SDA, Noël T. Technological Innovations in Photochemistry for Organic Synthesis: Flow Chemistry, High-Throughput Experimentation, Scale-up, and Photoelectrochemistry. Chem Rev 2022; 122:2752-2906. [PMID: 34375082 PMCID: PMC8796205 DOI: 10.1021/acs.chemrev.1c00332] [Citation(s) in RCA: 208] [Impact Index Per Article: 104.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Indexed: 02/08/2023]
Abstract
Photoinduced chemical transformations have received in recent years a tremendous amount of attention, providing a plethora of opportunities to synthetic organic chemists. However, performing a photochemical transformation can be quite a challenge because of various issues related to the delivery of photons. These challenges have barred the widespread adoption of photochemical steps in the chemical industry. However, in the past decade, several technological innovations have led to more reproducible, selective, and scalable photoinduced reactions. Herein, we provide a comprehensive overview of these exciting technological advances, including flow chemistry, high-throughput experimentation, reactor design and scale-up, and the combination of photo- and electro-chemistry.
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Affiliation(s)
- Laura Buglioni
- Micro
Flow Chemistry and Synthetic Methodology, Department of Chemical Engineering
and Chemistry, Eindhoven University of Technology, Het Kranenveld, Bldg 14—Helix, 5600 MB, Eindhoven, The Netherlands
- Flow
Chemistry Group, van ’t Hoff Institute for Molecular Sciences
(HIMS), Universiteit van Amsterdam (UvA), Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Fabian Raymenants
- Flow
Chemistry Group, van ’t Hoff Institute for Molecular Sciences
(HIMS), Universiteit van Amsterdam (UvA), Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Aidan Slattery
- Flow
Chemistry Group, van ’t Hoff Institute for Molecular Sciences
(HIMS), Universiteit van Amsterdam (UvA), Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Stefan D. A. Zondag
- Flow
Chemistry Group, van ’t Hoff Institute for Molecular Sciences
(HIMS), Universiteit van Amsterdam (UvA), Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Timothy Noël
- Flow
Chemistry Group, van ’t Hoff Institute for Molecular Sciences
(HIMS), Universiteit van Amsterdam (UvA), Science Park 904, 1098 XH, Amsterdam, The Netherlands
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9
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Tay NES, Lehnherr D, Rovis T. Photons or Electrons? A Critical Comparison of Electrochemistry and Photoredox Catalysis for Organic Synthesis. Chem Rev 2022; 122:2487-2649. [PMID: 34751568 PMCID: PMC10021920 DOI: 10.1021/acs.chemrev.1c00384] [Citation(s) in RCA: 128] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Redox processes are at the heart of synthetic methods that rely on either electrochemistry or photoredox catalysis, but how do electrochemistry and photoredox catalysis compare? Both approaches provide access to high energy intermediates (e.g., radicals) that enable bond formations not constrained by the rules of ionic or 2 electron (e) mechanisms. Instead, they enable 1e mechanisms capable of bypassing electronic or steric limitations and protecting group requirements, thus enabling synthetic chemists to disconnect molecules in new and different ways. However, while providing access to similar intermediates, electrochemistry and photoredox catalysis differ in several physical chemistry principles. Understanding those differences can be key to designing new transformations and forging new bond disconnections. This review aims to highlight these differences and similarities between electrochemistry and photoredox catalysis by comparing their underlying physical chemistry principles and describing their impact on electrochemical and photochemical methods.
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Affiliation(s)
- Nicholas E S Tay
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Dan Lehnherr
- Process Research and Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Tomislav Rovis
- Department of Chemistry, Columbia University, New York, New York 10027, United States
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10
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Mandigma MJP, Žurauskas J, MacGregor CI, Edwards LJ, Shahin A, d'Heureuse L, Yip P, Birch DJS, Gruber T, Heilmann J, John MP, Barham JP. An organophotocatalytic late-stage N–CH3 oxidation of trialkylamines to N-formamides with O2 in continuous flow. Chem Sci 2022; 13:1912-1924. [PMID: 35308839 PMCID: PMC8849051 DOI: 10.1039/d1sc05840a] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 12/26/2021] [Indexed: 12/25/2022] Open
Abstract
We report an organophotocatalytic, N–CH3-selective oxidation of trialkylamines in continuous flow. Based on the 9,10-dicyanoanthracene (DCA) core, a new catalyst (DCAS) was designed with solubilizing groups for flow processing. This allowed O2 to be harnessed as a sustainable oxidant for late-stage photocatalytic N–CH3 oxidations of complex natural products and active pharmaceutical ingredients bearing functional groups not tolerated by previous methods. The organophotocatalytic gas–liquid flow process affords cleaner reactions than in batch mode, in short residence times of 13.5 min and productivities of up to 0.65 g per day. Spectroscopic and computational mechanistic studies showed that catalyst derivatization not only enhanced solubility of the new catalyst compared to poorly-soluble DCA, but profoundly diverted the photocatalytic mechanism from singlet electron transfer (SET) reductive quenching with amines toward energy transfer (EnT) with O2. An N–CH3-selective trialkylamine oxidation to N-formamides is reported in continuous flow using gaseous O2. A novel, enhanced-solubility dicyanoanthracene organophotocatalyst switched the photochemical mechanism from electron to energy transfer.![]()
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Affiliation(s)
- Mark John P. Mandigma
- Fakultät für Chemie und Pharmazie, Universität Regensburg, 93040 Regensburg, Germany
| | - Jonas Žurauskas
- Fakultät für Chemie und Pharmazie, Universität Regensburg, 93040 Regensburg, Germany
| | - Callum I. MacGregor
- GlaxoSmithKline Medicines Research Centre, Gunnels Wood Road, Stevenage SG1 2NY, UK
| | - Lee J. Edwards
- GlaxoSmithKline Medicines Research Centre, Gunnels Wood Road, Stevenage SG1 2NY, UK
| | - Ahmed Shahin
- Fakultät für Chemie und Pharmazie, Universität Regensburg, 93040 Regensburg, Germany
- Chemistry Department, Faculty of Science, Benha University, 13518 Benha, Egypt
| | - Ludwig d'Heureuse
- Fakultät für Chemie und Pharmazie, Universität Regensburg, 93040 Regensburg, Germany
| | - Philip Yip
- Department of Physics, SUPA, University of Strathclyde, 107 Rottenrow East, Glasgow, G4 0NG, UK
| | - David J. S. Birch
- Department of Physics, SUPA, University of Strathclyde, 107 Rottenrow East, Glasgow, G4 0NG, UK
| | - Thomas Gruber
- Fakultät für Chemie und Pharmazie, Universität Regensburg, 93040 Regensburg, Germany
| | - Jörg Heilmann
- Fakultät für Chemie und Pharmazie, Universität Regensburg, 93040 Regensburg, Germany
| | - Matthew P. John
- GlaxoSmithKline Medicines Research Centre, Gunnels Wood Road, Stevenage SG1 2NY, UK
| | - Joshua P. Barham
- Fakultät für Chemie und Pharmazie, Universität Regensburg, 93040 Regensburg, Germany
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11
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Roider T, Frommknecht N, Höltzel A, Tallarek U. Device for automated screening of irradiation wavelength and intensity – investigation of the wavelength dependence of photoreactions with an arylazo sulfone in continuous flow. REACT CHEM ENG 2022. [DOI: 10.1039/d2re00142j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A system allowing the automatic change of LED arrays (normalized to the number of emitted photons) is presented to study photochemical reactions in continuous flow for their wavelength dependence.
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Affiliation(s)
- Thomas Roider
- Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Norbert Frommknecht
- Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Alexandra Höltzel
- Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Ulrich Tallarek
- Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
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12
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Wicks C, Hudlicky T, Rinner U. Morphine alkaloids: History, biology, and synthesis. THE ALKALOIDS. CHEMISTRY AND BIOLOGY 2021; 86:145-342. [PMID: 34565506 DOI: 10.1016/bs.alkal.2021.04.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This chapter provides a short overview of the history of morphine since it's isolation by Sertürner in 1805. The biosynthesis of the title alkaloid as well as all total and formal syntheses of morphine and codeine published after 1996 are discussed in detail. The last section of this chapter provides a detailed overview of medicinally relevant derivatives of the title alkaloid.
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Affiliation(s)
- Christopher Wicks
- Department of Chemistry and Centre for Biotechnology, Brock University, St. Catharines, ON, Canada
| | - Tomas Hudlicky
- Department of Chemistry and Centre for Biotechnology, Brock University, St. Catharines, ON, Canada
| | - Uwe Rinner
- IMC Fachhochschule Krems/IMC University of Applied Sciences Krems, Krems, Austria.
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13
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Sommer F, Cantillo D, Kappe CO. A small footprint oxycodone generator based on continuous flow technology and real-time analytics. J Flow Chem 2021. [DOI: 10.1007/s41981-021-00193-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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14
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Najmi AA, Bhat MF, Bischoff R, Poelarends GJ, Permentier HP. TEMPO‐Mediated Electrochemical N‐demethylation of Opiate Alkaloids. ChemElectroChem 2021. [DOI: 10.1002/celc.202100784] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Ali Alipour Najmi
- Department of Analytical Biochemistry Groningen Research Institute of Pharmacy University of Groningen A. Deusinglaan 1 9713 AV Groningen The Netherlands
| | - M. Faizan Bhat
- Department of Chemical and Pharmaceutical Biology Groningen Research Institute of Pharmacy University of Groningen A. Deusinglaan 1 9713 AV Groningen The Netherlands
| | - Rainer Bischoff
- Department of Analytical Biochemistry Groningen Research Institute of Pharmacy University of Groningen A. Deusinglaan 1 9713 AV Groningen The Netherlands
| | - Gerrit J. Poelarends
- Department of Chemical and Pharmaceutical Biology Groningen Research Institute of Pharmacy University of Groningen A. Deusinglaan 1 9713 AV Groningen The Netherlands
| | - Hjalmar P. Permentier
- Department of Analytical Biochemistry Groningen Research Institute of Pharmacy University of Groningen A. Deusinglaan 1 9713 AV Groningen The Netherlands
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15
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Talukdar R. Tracking down the brominated single electron oxidants in recent organic red-ox transformations: photolysis and photocatalysis. Org Biomol Chem 2020; 18:8294-8345. [PMID: 33020775 DOI: 10.1039/d0ob01652g] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A wide range of organic and inorganic brominated compounds including molecular bromine have been extensively used as oxidants in many organic photo-redox transformations in recent years, an area of ever growing interest because of greener and milder approaches. The oxidation power of these compounds is utilized through both mechanistic pathways (by hydrogen atom transfer or HAT in the absence of a photocatalyst and a combination of single electron transfer or SET and/or HAT in the presence of a photocatalyst). Not only as terminal oxidants for regeneration of photocatalysts, but brominated reactants have also contributed to the oxidation of the reaction intermediate(s) to carry on the radical chain process in several reactions. Here in this review mainly the non-brominative oxidative product formations are discussed, carried out since the last two decades, skipping the instances where they acted as terminal oxidants only to regenerate photocatalysts. The reactions are used to generate natural products, pharmaceuticals and beyond.
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Affiliation(s)
- Ranadeep Talukdar
- Molecular Synthesis and Drug Discovery Laboratory, Centre of Biomedical Research, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow-226014, India.
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16
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Glotz G, Kappe CO, Cantillo D. Electrochemical N-Demethylation of 14-Hydroxy Morphinans: Sustainable Access to Opioid Antagonists. Org Lett 2020; 22:6891-6896. [PMID: 32790319 PMCID: PMC7498191 DOI: 10.1021/acs.orglett.0c02424] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Indexed: 11/28/2022]
Abstract
The most challenging step in the preparation of many opioid antagonists is the selective N-demethylation of a 14-hydroxymorphinan precursor. This process is carried out on a large scale using stoichiometric amounts of hazardous chemicals like cyanogen bromide or chloroformates. We have developed a mild reagent- and catalyst-free procedure for the N-demethylation step based on the anodic oxidation of the tertiary amine. The ensuing intermediates can be readily hydrolyzed to the target nor-opioids in very good yields.
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Affiliation(s)
- Gabriel Glotz
- Institute
of Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
- Center
for Continuous Flow Synthesis and Processing (CC FLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010 Graz, Austria
| | - C. Oliver Kappe
- Institute
of Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
- Center
for Continuous Flow Synthesis and Processing (CC FLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010 Graz, Austria
| | - David Cantillo
- Institute
of Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
- Center
for Continuous Flow Synthesis and Processing (CC FLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010 Graz, Austria
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17
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Chen Y, Glotz G, Cantillo D, Kappe CO. Organophotocatalytic N-Demethylation of Oxycodone Using Molecular Oxygen. Chemistry 2020; 26:2973-2979. [PMID: 31898822 PMCID: PMC7317935 DOI: 10.1002/chem.201905505] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 01/02/2020] [Indexed: 11/20/2022]
Abstract
N‐Demethylation of oxycodone is one of the key steps in the synthesis of important opioid antagonists like naloxone or analgesics like nalbuphine. The reaction is typically carried out using stoichiometric amounts of toxic and corrosive reagents. Herein, we present a green and scalable organophotocatalytic procedure that accomplishes the N‐demethylation step using molecular oxygen as the terminal oxidant and an organic dye (rose bengal) as an effective photocatalyst. Optimization of the reaction conditions under continuous flow conditions using visible‐light irradiation led to an efficient, reliable, and scalable process, producing noroxycodone hydrochloride in high isolated yield and purity after a simple workup.
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Affiliation(s)
- Yuesu Chen
- Center for Continuous Flow Synthesis and Processing (CC FLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010, Graz, Austria.,Institute of Chemistry, University of Graz, Heinrichstrasse 28, 8010, Graz, Austria
| | - Gabriel Glotz
- Center for Continuous Flow Synthesis and Processing (CC FLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010, Graz, Austria.,Institute of Chemistry, University of Graz, Heinrichstrasse 28, 8010, Graz, Austria
| | - David Cantillo
- Center for Continuous Flow Synthesis and Processing (CC FLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010, Graz, Austria.,Institute of Chemistry, University of Graz, Heinrichstrasse 28, 8010, Graz, Austria
| | - C Oliver Kappe
- Center for Continuous Flow Synthesis and Processing (CC FLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010, Graz, Austria.,Institute of Chemistry, University of Graz, Heinrichstrasse 28, 8010, Graz, Austria
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