1
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Dhayalan V, Dandela R, Devi KB, Dhanusuraman R. Synthesis and Applications of Asymmetric Catalysis Using Chiral Ligands Containing Quinoline Motifs. SYNOPEN 2022. [DOI: 10.1055/a-1743-4534] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
In the past decade, asymmetric synthesis of chiral ligands containing quinoline motifs, a family of natural products displaying a broad range of structural diversity and their metal complexes have become the most significant methodology for the generation of enantiomerically pure compounds of biological and pharmaceutical interest. This review provides comprehensive insight on the plethora of nitrogen-based chiral ligands containing quinoline motifs and organocatalysts used in asymmetric synthesis. However, it is circumscribed to the synthesis of quinoline-based chiral ligands and metal complexes, and their applications in asymmetric synthesis as a homogeneous and heterogeneous catalyst.
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Affiliation(s)
- Vasudevan Dhayalan
- Department of Chemistry, National Institute of Technology Puducherry, Karaikal, India
| | - Rambabu Dandela
- Dept. of Industrial and Engineering Chemistry, Institute of Chemical Technology- IOC Bhubaneswar, Bhubaneswar, India
| | - K. Bavya Devi
- Department of Chemistry, Thassim Beevi Adbul Kader College for Women, Kilakarai, India
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2
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Juliá F, Constantin T, Leonori D. Applications of Halogen-Atom Transfer (XAT) for the Generation of Carbon Radicals in Synthetic Photochemistry and Photocatalysis. Chem Rev 2021; 122:2292-2352. [PMID: 34882396 DOI: 10.1021/acs.chemrev.1c00558] [Citation(s) in RCA: 162] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The halogen-atom transfer (XAT) is one of the most important and applied processes for the generation of carbon radicals in synthetic chemistry. In this review, we summarize and highlight the most important aspects associated with XAT and the impact it has had on photochemistry and photocatalysis. The organization of the material starts with the analysis of the most important mechanistic aspects and then follows a subdivision based on the nature of the reagents used in the halogen abstraction. This review aims to provide a general overview of the fundamental concepts and main agents involved in XAT processes with the objective of offering a tool to understand and facilitate the development of new synthetic radical strategies.
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Affiliation(s)
- Fabio Juliá
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Timothée Constantin
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Daniele Leonori
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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3
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Li M, Banerjee K, Friestad GK. Diastereocontrol in Radical Addition to β-Benzyloxy Hydrazones: Revised Approach to Tubuvaline and Synthesis of O-Benzyltubulysin V Benzyl Ester. J Org Chem 2021; 86:15139-15152. [PMID: 34636574 PMCID: PMC8576829 DOI: 10.1021/acs.joc.1c01798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Indexed: 11/29/2022]
Abstract
Radical addition to chiral N-acylhydrazones has generated unusual amino acids tubuphenylalanine (Tup) and tubuvaline (Tuv) that are structural components of the tubulysin family of picomolar antimitotic agents and previously led to a tubulysin tetrapeptide analog with a C-terminal alcohol. To improve efficiency in this synthetic route to tubulysins, and to address difficulties in oxidation of the C-terminal alcohol, here we present two alternative routes to Tuv that (a) improve step economy, (b) provide modified conditions for Mn-mediated radical addition in the presence of aromatic heterocycles, and (c) expose an example of double diastereocontrol in radical addition to a β-benzyloxyhydrazone with broader implications for asymmetric amine synthesis via radical addition. An efficient coupling sequence affords 11-O-benzyltubulysin V benzyl ester.
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Affiliation(s)
- Manshu Li
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Koushik Banerjee
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Gregory K. Friestad
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
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4
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5
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Nam TK, Jang DO. A synthetic route toward α,α-dialkyl α-amino ester derivatives via radical addition to hydrazone derivatives of α-ketoesters under “on-water” conditions. Tetrahedron Lett 2020. [DOI: 10.1016/j.tetlet.2019.151411] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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6
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Cullen STJ, Friestad GK. Alkyl Radical Addition to Aliphatic and Aromatic N-Acylhydrazones Using an Organic Photoredox Catalyst. Org Lett 2019; 21:8290-8294. [PMID: 31560554 PMCID: PMC6900872 DOI: 10.1021/acs.orglett.9b03053] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Increased versatility of intermolecular radical addition to imino acceptors via photoredox catalysis is reported. Primary and secondary radicals, generated via visible-light photocatalysis from alkyl biscatecholatosilicates with organocatalyst 4CzIPN, add successfully to both aromatic and aliphatic N-acylhydrazones in the presence of MgCl2. With N-benzoylhydrazones, a simple reductive cleavage of the N-N bond of the hydrazine adduct furnishes the free amine. Synthetic utility is exemplified in a synthetic application toward repaglinide, a clinically important hypoglycemic agent.
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Affiliation(s)
- Stephen T. J. Cullen
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Gregory K. Friestad
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
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7
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Liu XY, Qin Y. Indole Alkaloid Synthesis Facilitated by Photoredox Catalytic Radical Cascade Reactions. Acc Chem Res 2019; 52:1877-1891. [PMID: 31264824 DOI: 10.1021/acs.accounts.9b00246] [Citation(s) in RCA: 123] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The monoterpene indole alkaloids, containing over 3000 known members and more than 40 structural types, represent one of the largest natural product families that have proven to be an important drug source. Their complex chemical structures and significant biological activities have rendered these alkaloids attractive targets in the synthetic community for decades. While chemists have developed many synthetic methodologies and tactics toward this end, general strategies allowing divergent access to a large variety of structural types and members of monoterpene indole alkaloids are still limited and highly desirable. Photoredox catalysis has emerged in recent years as a powerful tool to realize chemical transformations via single electron transfer (SET) processes that would otherwise be inaccessible. In particular, when the radical species generated by the visible light photoinduced approach is involved in well-designed cascade reactions, the formation of multiple chemical bonds and the assembly of structurally complex molecules would be secured in a green and economic manner. This protocol might serve to remodel the way of thinking for the preparation of useful pharmaceuticals and complex natural products. Due to a long-standing interest in the synthesis of diverse indole alkaloids, our group previously developed a cyclopropanation strategy ( Qin , Y. Acc. Chem. Res. 2011 , 44 , 447 ) that was versatile to access several intriguing indole alkaloid molecules. With an idea of developing more general synthetic approaches to as many members of various indole alkaloids as possible, we recently disclosed new radical cascade reactions enabled by photoredox catalysis, leading to the collective asymmetric total synthesis of 42 monoterpene indole alkaloids belonging to 7 structural types. Several important discoveries deserve to be highlighted. First, the use of photocatalytic technology allowed us to achieve an unusual reaction pathway that reversed the conventional reactivity between two nucleophilic amine and enamine groups. Second, a crucial nitrogen-centered radical, directly generated from a sulfonamide N-H bond, triggered three types of cascade reactions to deliver indole alkaloid cores with manifold functionalities and controllable diastereoselectivities. Moreover, expansion of this catalytic, scalable, and general methodology permitted the total synthesis of a large collection of indole alkaloids. In this Account, we wish to provide a complete picture of our studies concerning the original synthetic design, method development, and applications in total synthesis. It is anticipated that the visible-light-driven cascade strategy will find further utility in the realm of natural product synthesis.
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Affiliation(s)
- Xiao-Yu Liu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Yong Qin
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
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8
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Ni S, Padial NM, Kingston C, Vantourout JC, Schmitt DC, Edwards JT, Kruszyk MM, Merchant RR, Mykhailiuk PK, Sanchez BB, Yang S, Perry MA, Gallego GM, Mousseau JJ, Collins MR, Cherney RJ, Lebed PS, Chen JS, Qin T, Baran PS. A Radical Approach to Anionic Chemistry: Synthesis of Ketones, Alcohols, and Amines. J Am Chem Soc 2019; 141:6726-6739. [PMID: 30943023 DOI: 10.1021/jacs.9b02238] [Citation(s) in RCA: 130] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Historically accessed through two-electron, anionic chemistry, ketones, alcohols, and amines are of foundational importance to the practice of organic synthesis. After placing this work in proper historical context, this Article reports the development, full scope, and a mechanistic picture for a strikingly different way of forging such functional groups. Thus, carboxylic acids, once converted to redox-active esters (RAEs), can be utilized as formally nucleophilic coupling partners with other carboxylic derivatives (to produce ketones), imines (to produce benzylic amines), or aldehydes (to produce alcohols). The reactions are uniformly mild, operationally simple, and, in the case of ketone synthesis, broad in scope (including several applications to the simplification of synthetic problems and to parallel synthesis). Finally, an extensive mechanistic study of the ketone synthesis is performed to trace the elementary steps of the catalytic cycle and provide the end-user with a clear and understandable rationale for the selectivity, role of additives, and underlying driving forces involved.
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Affiliation(s)
- Shengyang Ni
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Natalia M Padial
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Cian Kingston
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Julien C Vantourout
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Daniel C Schmitt
- Pfizer Medicinal Sciences , Eastern Point Road , Groton , Connecticut 06340 , United States
| | - Jacob T Edwards
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Monika M Kruszyk
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Rohan R Merchant
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Pavel K Mykhailiuk
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States.,Enamine Ltd. , Chervonotkatska 78 , 02094 Kyiv , Ukraine.,Chemistry Department , Taras Shevchenko National University of Kyiv , Volodymyrska 64 , 01601 Kyiv , Ukraine
| | - Brittany B Sanchez
- Automated Synthesis Facility , Scripps Research , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Shouliang Yang
- Department of Chemistry , La Jolla Laboratories , Pfizer 10770 Science Center Drive , San Diego , California 92121 , United States
| | - Matthew A Perry
- Pfizer Medicinal Sciences , Eastern Point Road , Groton , Connecticut 06340 , United States
| | - Gary M Gallego
- Department of Chemistry , La Jolla Laboratories , Pfizer 10770 Science Center Drive , San Diego , California 92121 , United States
| | - James J Mousseau
- Pfizer Medicinal Sciences , Eastern Point Road , Groton , Connecticut 06340 , United States
| | - Michael R Collins
- Department of Chemistry , La Jolla Laboratories , Pfizer 10770 Science Center Drive , San Diego , California 92121 , United States
| | - Robert J Cherney
- Research & Development , Bristol-Myers Squibb Company , Rt. 206 & Province Line Road , Princeton , New Jersey 08543 , United States
| | - Pavlo S Lebed
- Enamine Ltd. , Chervonotkatska 78 , 02094 Kyiv , Ukraine.,ChemBioCenter , Taras Shevchenko National University of Kyiv , Volodymyrska 64 , 01601 Kyiv , Ukraine
| | - Jason S Chen
- Automated Synthesis Facility , Scripps Research , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Tian Qin
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Phil S Baran
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
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9
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de Resende Filho JBM, Falcão NKSM, Pires GP, de Vasconcelos LFS, Pinheiro SM, dos Santos Filho JM, Frazão Barbosa MI, Doriguetto AC, Teotonio EES, Vale JA. Lanthanide–EDTA complexes covalently bonded on Fe 3O 4@SiO 2 magnetic nanoparticles promote the green, stereoselective synthesis of N-acylhydrazones. NEW J CHEM 2019. [DOI: 10.1039/c9nj02916h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Highly efficient stereoselective synthesis of E–N-acylhydrazones using magnetic nanoparticles-Ln3+ as heterogeneous catalysts.
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Affiliation(s)
| | | | - Gilvan P. Pires
- Departamento de Química
- Universidade Federal da Paraíba
- 58051-970 João Pessoa-PB
- Brazil
| | | | - Sávio M. Pinheiro
- Departamento de Química
- Universidade Federal da Paraíba
- 58051-970 João Pessoa-PB
- Brazil
| | - José Maurício dos Santos Filho
- Laboratório de Planejamento e Síntese Aplicados à Química Medicinal – SintMed®
- Universidade Federal de Pernambuco
- Recife
- Brazil
| | | | | | | | - Juliana A. Vale
- Departamento de Química
- Universidade Federal da Paraíba
- 58051-970 João Pessoa-PB
- Brazil
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10
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Liu W, Qin W, Wang X, Xue F, Liu XY, Qin Y. Bioinspired Synthesis of (+)-Cinchonidine Using Cascade Reactions. Angew Chem Int Ed Engl 2018; 57:12299-12302. [PMID: 30084528 DOI: 10.1002/anie.201804848] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 07/09/2018] [Indexed: 11/06/2022]
Abstract
The development of efficient syntheses of complex natural products has long been a major challenge in synthetic chemistry. Designing cascade reactions and employing bioinspired transformations are an important and reliable means of achieving this goal. Presented here is a combination of these two strategies, which allow efficient asymmetric synthesis of the cinchona alkaloid (+)-cinchonidine. The key steps of this synthesis are a controllable, visible-light-induced photoredox radical cascade reaction to efficiently access the tetracyclic monoterpenoid indole alkaloid core, as well as a practical biomimetic cascade rearrangement for the indole to quinoline transformation. The use of stereoselective chemical transformations in this work makes it an efficient synthesis of (+)-cinchonidine.
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Affiliation(s)
- Wentao Liu
- School of Pharmaceutic Science, Chongqing University, Chongqing, 401331, P. R. China
| | - Wenfang Qin
- School of Pharmaceutic Science, Chongqing University, Chongqing, 401331, P. R. China
| | - Xiaobei Wang
- Key Laboratory of Drug Targeting and Drug Delivery Systems of the Ministry of Education, and Sichuan Engineering Laboratory for Plant-Sourced Drug and Research Center for Drug Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu, 610041, P. R. China
| | - Fei Xue
- Key Laboratory of Drug Targeting and Drug Delivery Systems of the Ministry of Education, and Sichuan Engineering Laboratory for Plant-Sourced Drug and Research Center for Drug Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu, 610041, P. R. China
| | - Xiao-Yu Liu
- Key Laboratory of Drug Targeting and Drug Delivery Systems of the Ministry of Education, and Sichuan Engineering Laboratory for Plant-Sourced Drug and Research Center for Drug Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu, 610041, P. R. China
| | - Yong Qin
- Key Laboratory of Drug Targeting and Drug Delivery Systems of the Ministry of Education, and Sichuan Engineering Laboratory for Plant-Sourced Drug and Research Center for Drug Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu, 610041, P. R. China
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11
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Liu W, Qin W, Wang X, Xue F, Liu XY, Qin Y. Bioinspired Synthesis of (+)-Cinchonidine Using Cascade Reactions. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201804848] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Wentao Liu
- School of Pharmaceutic Science; Chongqing University; Chongqing 401331 P. R. China
| | - Wenfang Qin
- School of Pharmaceutic Science; Chongqing University; Chongqing 401331 P. R. China
| | - Xiaobei Wang
- Key Laboratory of Drug Targeting and Drug Delivery Systems of the Ministry of Education; and Sichuan Engineering Laboratory for Plant-Sourced Drug and Research Center for Drug Industrial Technology; West China School of Pharmacy; Sichuan University; Chengdu 610041 P. R. China
| | - Fei Xue
- Key Laboratory of Drug Targeting and Drug Delivery Systems of the Ministry of Education; and Sichuan Engineering Laboratory for Plant-Sourced Drug and Research Center for Drug Industrial Technology; West China School of Pharmacy; Sichuan University; Chengdu 610041 P. R. China
| | - Xiao-Yu Liu
- Key Laboratory of Drug Targeting and Drug Delivery Systems of the Ministry of Education; and Sichuan Engineering Laboratory for Plant-Sourced Drug and Research Center for Drug Industrial Technology; West China School of Pharmacy; Sichuan University; Chengdu 610041 P. R. China
| | - Yong Qin
- Key Laboratory of Drug Targeting and Drug Delivery Systems of the Ministry of Education; and Sichuan Engineering Laboratory for Plant-Sourced Drug and Research Center for Drug Industrial Technology; West China School of Pharmacy; Sichuan University; Chengdu 610041 P. R. China
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12
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Patel NR, Kelly CB, Siegenfeld AP, Molander GA. Mild, Redox-Neutral Alkylation of Imines Enabled by an Organic Photocatalyst. ACS Catal 2017; 7:1766-1770. [PMID: 28367354 PMCID: PMC5369175 DOI: 10.1021/acscatal.6b03665] [Citation(s) in RCA: 119] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Revised: 01/27/2017] [Indexed: 12/02/2022]
Abstract
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An operationally simple, mild, redox-neutral
method for the photoredox
alkylation of imines is reported. Utilizing an inexpensive organic
photoredox catalyst, alkyl radicals are readily generated from the
single-electron oxidation of ammonium alkyl bis(catecholato)silicates
and are subsequently engaged in a C–C bond-forming reaction
with imines. The process is highly selective, metal-free, and does
not require a large excess of the alkylating reagent or the use of
acidic additives.
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Affiliation(s)
- Niki R. Patel
- Roy and Diana Vagelos Laboratories,
Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, United States
| | - Christopher B. Kelly
- Roy and Diana Vagelos Laboratories,
Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, United States
| | - Allison P. Siegenfeld
- Roy and Diana Vagelos Laboratories,
Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, United States
| | - Gary A. Molander
- Roy and Diana Vagelos Laboratories,
Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, United States
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13
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A simple and efficient approach to the N-amination of oxazolidinones using monochloroamine. Tetrahedron Lett 2016. [DOI: 10.1016/j.tetlet.2016.09.034] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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14
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Friestad GK, Banerjee K, Marié JC, Mali U, Yao L. Stereoselective access to tubuphenylalanine and tubuvaline: improved Mn-mediated radical additions and assembly of a tubulysin tetrapeptide analog. J Antibiot (Tokyo) 2016; 69:294-8. [PMID: 26883395 PMCID: PMC4924578 DOI: 10.1038/ja.2016.7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 01/12/2016] [Accepted: 01/18/2016] [Indexed: 01/05/2023]
Abstract
Synthesis of tubuphenylalanine and tubuvaline (Tuv), α-substituted γ-amino acid building blocks for tubulysin family of antimitotic compounds, has been improved using a radical addition reaction in the presence of unprotected hydroxyl functionality. The key carbon-carbon bond construction entails stereoselective Mn-mediated photolytic additions of alkyl iodides to the C=N bond of chiral N-acylhydrazones, and generates the chiral amines in high yield with complete stereocontrol. Reductive N-N bond cleavage and alcohol oxidation converted these amino alcohols into the corresponding γ-amino acids. The route to Tuv proceeded via peptide coupling with serine methyl ester, followed by a high-yielding sequence to convert the serine amide to a thiazole. Finally, peptide bond construction established the tubulysin framework in the form of a C-terminal alcohol analog. Attempted oxidation to the C-terminal carboxylate was unsuccessful; control experiments with dipeptide 18 showed a cyclization interfered with the desired oxidation process.
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Affiliation(s)
| | - Koushik Banerjee
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242 USA
| | | | - Umesh Mali
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242 USA
| | - Lei Yao
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242 USA
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15
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Chen M, Zhong M, Johnson JA. Light-Controlled Radical Polymerization: Mechanisms, Methods, and Applications. Chem Rev 2016; 116:10167-211. [PMID: 26978484 DOI: 10.1021/acs.chemrev.5b00671] [Citation(s) in RCA: 688] [Impact Index Per Article: 86.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The use of light to mediate controlled radical polymerization has emerged as a powerful strategy for rational polymer synthesis and advanced materials fabrication. This review provides a comprehensive survey of photocontrolled, living radical polymerizations (photo-CRPs). From the perspective of mechanism, all known photo-CRPs are divided into either (1) intramolecular photochemical processes or (2) photoredox processes. Within these mechanistic regimes, a large number of methods are summarized and further classified into subcategories based on the specific reagents, catalysts, etc., involved. To provide a clear understanding of each subcategory, reaction mechanisms are discussed. In addition, applications of photo-CRP reported so far, which include surface fabrication, particle preparation, photoresponsive gel design, and continuous flow technology, are summarized. We hope this review will not only provide informative knowledge to researchers in this field but also stimulate new ideas and applications to further advance photocontrolled reactions.
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Affiliation(s)
- Mao Chen
- Department of Chemistry and ‡Department of Chemical Engineering, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Mingjiang Zhong
- Department of Chemistry and ‡Department of Chemical Engineering, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Jeremiah A Johnson
- Department of Chemistry and ‡Department of Chemical Engineering, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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16
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Slater KA, Friestad GK. Mn-Mediated Radical-Ionic Annulations of Chiral N-Acylhydrazones. J Org Chem 2015; 80:6432-40. [DOI: 10.1021/acs.joc.5b00863] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kara A. Slater
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Gregory K. Friestad
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
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17
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Schiedler DA, Vellucci JK, Lu Y, Beaudry CM. The development of carbon–carbon bond forming reactions of aminal radicals. Tetrahedron 2015. [DOI: 10.1016/j.tet.2014.12.067] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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18
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Rossi B, Pastori N, Prosperini S, Punta C. Multicomponent versus domino reactions: One-pot free-radical synthesis of β-amino-ethers and β-amino-alcohols. Beilstein J Org Chem 2015; 11:66-73. [PMID: 25670994 PMCID: PMC4311587 DOI: 10.3762/bjoc.11.10] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 01/06/2015] [Indexed: 11/24/2022] Open
Abstract
Following an optimized multicomponent procedure, an aryl amine, a ketone, and a cyclic ether or an alcohol molecule are assembled in a one-pot synthesis by nucleophilic radical addition of ketyl radicals to ketimines generated in situ. The reaction occurs under mild conditions by mediation of the TiCl4/Zn/t-BuOOH system, leading to the formation of quaternary β-amino-ethers and -alcohols. The new reaction conditions guarantee good selectivity by preventing the formation of secondary products. The secondary products are possibly derived from a competitive domino reaction, which involves further oxidation of the ketyl radicals.
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Affiliation(s)
- Bianca Rossi
- Department of Chemistry, Materials, and Chemical Engineering "G. Natta" - Politecnico di Milano, Via Leonardo da Vinci 32, I-20131 Milano, Italy; Fax (+39)0223993180
| | - Nadia Pastori
- Department of Chemistry, Materials, and Chemical Engineering "G. Natta" - Politecnico di Milano, Via Leonardo da Vinci 32, I-20131 Milano, Italy; Fax (+39)0223993180
| | - Simona Prosperini
- Department of Chemistry, Materials, and Chemical Engineering "G. Natta" - Politecnico di Milano, Via Leonardo da Vinci 32, I-20131 Milano, Italy; Fax (+39)0223993180
| | - Carlo Punta
- Department of Chemistry, Materials, and Chemical Engineering "G. Natta" - Politecnico di Milano, Via Leonardo da Vinci 32, I-20131 Milano, Italy; Fax (+39)0223993180
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dos Santos Filho JM. Mild, Stereoselective, and Highly Efficient Synthesis ofN-Acylhydrazones Mediated by CeCl3·7H2O in a Broad Range of Solvents. European J Org Chem 2014. [DOI: 10.1002/ejoc.201402609] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Fernández-Salas JA, Rodríguez-Fernández MM, Maestro MC, García-Ruano JL. Synthesis of Enantiomerically Pure (α-Phenylalkyl)amines with Substituents at theorthoPosition through Diastereoselective Radical Alkylation Reaction of Sulfinimines. European J Org Chem 2014. [DOI: 10.1002/ejoc.201402355] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Miyata O, Ueda M, Ito Y, Matsuda N, Nishida Y. Sequential Radical Addition and Fischer-Type Indolization Reactions of Conjugated Hydrazones for the Preparation of α-Alkylindole-3-acetic Acids. HETEROCYCLES 2014. [DOI: 10.3987/com-14-12957] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Charette AB, Lindsay V. Stereoselective formation of amines by nucleophilic addition to azomethine derivatives. Top Curr Chem (Cham) 2014; 343:33-73. [PMID: 24233253 DOI: 10.1007/128_2013_492] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
This chapter describes state-of-the-art methods to prepare α-chiral amines by the addition of nonstabilized nucleophiles to imine derivatives. The first part of the chapter illustrates the most effective diastereoselective addition reaction (substrate controlled and chiral auxiliary based methods) whereas the second part focuses on catalytic asymmetric methods.
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Friestad GK. Control of asymmetry in the radical addition approach to chiral amine synthesis. Top Curr Chem (Cham) 2014; 343:1-32. [PMID: 24085561 PMCID: PMC4114248 DOI: 10.1007/128_2013_481] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The state-of-the-science in asymmetric free radical additions to imino compounds is presented, beginning with an overview of methods involving stereocontrol by various chiral auxiliary approaches. Chiral N-acylhydrazones are discussed with respect to their use as radical acceptors for Mn-mediated intermolecular additions, from design to scope surveys to applications to biologically active targets. A variety of aldehydes and ketones serve as viable precursors for the chiral hydrazones, and a variety of alkyl iodides may be employed as radical precursors, as discussed in a critical review of the functional group compatibility of the reaction. Applications to amino acid and alkaloid synthesis are presented to illustrate the synthetic potential of these versatile stereocontrolled carbon-carbon bond construction reactions. Asymmetric catalysis is discussed, from seminal work on the stereocontrol of radical addition to imino compounds by non-covalent interactions with stoichiometric amounts of catalysts, to more recent examples demonstrating catalyst turnover.
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Fernández-Salas JA, Maestro MC, Rodríguez-Fernández MM, García-Ruano JL, Alonso I. Intermolecular alkyl radical additions to enantiopure N-tert-butanesulfinyl aldimines. Org Lett 2013; 15:1658-61. [PMID: 23484734 DOI: 10.1021/ol400439g] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The sulfinyl group in (R)-N-tert-butanesulfinyl aldimines provides efficient control of the stereoselectivity in the intermolecular reactions with alkyl radicals. The methodology is applicable to aryl, heteroaryl, benzyl, and alkynyl imines, even those containing CN, CO2Me, COR, and OH groups. The best results are attained with hindered radicals (tertiary and secondary ones) without C═N bond reduction. This reaction complements the well-established organometallic additions to N-sulfinyl aldimines to obtain enantiomerically pure functionalized α-branched primary amines.
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Affiliation(s)
- José A Fernández-Salas
- Departamento de Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049-Cantoblanco, Madrid, Spain
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Rossi B, Prosperini S, Pastori N, Clerici A, Punta C. New advances in titanium-mediated free radical reactions. Molecules 2012; 17:14700-32. [PMID: 23519248 PMCID: PMC6268425 DOI: 10.3390/molecules171214700] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 11/28/2012] [Accepted: 12/06/2012] [Indexed: 01/11/2023] Open
Abstract
Titanium complexes have been widely used as catalysts for C‑C bond-forming processes via free-radical routes. Herein we provide an overview of some of the most significant contributions in the field, that covers the last decade, emphasizing the key role played by titanium salts in the promotion of selective reactions aimed at the synthesis of multifunctional organic compounds, including nucleophilic radical additions to imines, pinacol and coupling reactions, ring opening of epoxides and living polymerization.
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Affiliation(s)
- Bianca Rossi
- Department of Chemistry, Materials, and Chemical Engineering “Giulio Natta”, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133 Milano, Italy; E-Mails: (B.R.); (S.P.); (N.P.); (A.C.)
| | - Simona Prosperini
- Department of Chemistry, Materials, and Chemical Engineering “Giulio Natta”, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133 Milano, Italy; E-Mails: (B.R.); (S.P.); (N.P.); (A.C.)
- INSTM (National Consortium for Materials Science and Technology) Local Unit, Politecnico di Milano, 20133 Milan, Italy
| | - Nadia Pastori
- Department of Chemistry, Materials, and Chemical Engineering “Giulio Natta”, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133 Milano, Italy; E-Mails: (B.R.); (S.P.); (N.P.); (A.C.)
| | - Angelo Clerici
- Department of Chemistry, Materials, and Chemical Engineering “Giulio Natta”, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133 Milano, Italy; E-Mails: (B.R.); (S.P.); (N.P.); (A.C.)
| | - Carlo Punta
- Department of Chemistry, Materials, and Chemical Engineering “Giulio Natta”, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133 Milano, Italy; E-Mails: (B.R.); (S.P.); (N.P.); (A.C.)
- INSTM (National Consortium for Materials Science and Technology) Local Unit, Politecnico di Milano, 20133 Milan, Italy
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