1
|
Lim SH, Kim MJ, Wee KR, Lim DH, Kim YI, Cho DW. Silyl Tether-Assisted Photooxygenation of Electron-Deficient Enaminoesters: Direct Access to Oxamate Formation. J Org Chem 2023; 88:172-188. [PMID: 36516444 DOI: 10.1021/acs.joc.2c02101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Photooxygenation reactions of electron-deficient enaminoesters bearing an oxophilic silyl tether at the α-position of the nitrogen atom using methylene blue (MB) were explored to develop a mild and efficient photochemical strategy for oxidative C-C double bond cleavage reactions via singlet oxygen (1O2). Photochemically generated 1O2, through energy transfer from the triplet excited state of MB (3MB*) to molecular oxygen (3O2), was added across a C-C double bond moiety of enaminoesters to form perepoxides, which rearranged to form dioxetane intermediates. The cycloreversion of the formed dioxetane via both C-C and O-O bond cleavage processes led to the formation of oxamates. Importantly, contrary to alkyl group tether-substituted electron-deficient enaminoesters that typically disfavor photooxygenation, the silyl tether-substituted analogues undergo this photochemical transformation efficiently with the assistance of a silyl tether, which facilitates formation of the perepoxide. The observations in this study provide useful information about photosensitized oxygenation reactions of unsaturated C-C bonds, and, moreover, this photochemical strategy can be utilized as a mild and feasible method for the preparation of diversely functionalized carbonyl compounds including oxamates.
Collapse
Affiliation(s)
- Suk Hyun Lim
- Department of Chemistry, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Korea
| | - Min-Ji Kim
- Department of Chemistry, Daegu University, Gyeongsan, Gyeongbuk 38453, Korea
| | - Kyung-Ryang Wee
- Department of Chemistry, Daegu University, Gyeongsan, Gyeongbuk 38453, Korea
| | - Dong Hyun Lim
- Department of Chemistry, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Korea
| | - Young-Il Kim
- Department of Chemistry, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Korea
| | - Dae Won Cho
- Department of Chemistry, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Korea
| |
Collapse
|
2
|
Orfanopoulos M. Singlet Oxygen: Discovery, Chemistry, C 60 -Sensitization †. Photochem Photobiol 2021; 97:1182-1218. [PMID: 34240450 DOI: 10.1111/php.13486] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 07/04/2021] [Indexed: 01/11/2023]
Abstract
This review article refers to the discovery of excited molecular oxygen, in particular on its lower singlet excited state (1 Δg , 1 O2 ). After a short report on singlet oxygen generation, the review is focused on the chemistry of this reactive species. Specifically, the three major reactions of 1 O2 with unsaturated organic substrates, namely the [4 + 2] and [2 +2] cycloadditions as well as the ene reaction, are reviewed. The proposed mechanisms of these reactions, through the years, based on experimental and computational work, have been presented. Selected examples of singlet oxygen-synthetic applications are also mentioned. The [60]fullerene and fullereno-materials photosensitized oxidations in homogeneous, as well as in heterogeneous conditions, are also comprehensively discussed. Finally, the self-sensitized photooxidation of open cage fullerenes as well as fullerenes bearing oxidizable groups is reported.
Collapse
|
3
|
Costa E Silva R, Oliveira da Silva L, de Andrade Bartolomeu A, Brocksom TJ, de Oliveira KT. Recent applications of porphyrins as photocatalysts in organic synthesis: batch and continuous flow approaches. Beilstein J Org Chem 2020; 16:917-955. [PMID: 32461773 PMCID: PMC7214915 DOI: 10.3762/bjoc.16.83] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 04/22/2020] [Indexed: 12/26/2022] Open
Abstract
In this review we present relevant and recent applications of porphyrin derivatives as photocatalysts in organic synthesis, involving both single electron transfer (SET) and energy transfer (ET) mechanistic approaches. We demonstrate that these highly conjugated photosensitizers show increasing potential in photocatalysis since they combine both photo- and electrochemical properties which can substitute available metalloorganic photocatalysts. Batch and continuous-flow approaches are presented highlighting the relevance of enabling technologies for the renewal of porphyrin applications in photocatalysis. Finally, the reaction scale in which the methodologies were developed are highlighted since this is an important parameter in the authors' opinion.
Collapse
Affiliation(s)
- Rodrigo Costa E Silva
- Departamento de Química, Universidade Federal de São Carlos, São Carlos, SP, 13565-905, Brazil
| | - Luely Oliveira da Silva
- Departamento de Química, Universidade Federal de São Carlos, São Carlos, SP, 13565-905, Brazil.,Departamento de Ciências Naturais, Universidade do Estado do Pará, Marabá, PA, 68502-100, Brazil
| | | | - Timothy John Brocksom
- Departamento de Química, Universidade Federal de São Carlos, São Carlos, SP, 13565-905, Brazil
| | | |
Collapse
|
4
|
Affiliation(s)
- Ashwini A. Ghogare
- Department
of Chemistry, Brooklyn College, 2900 Bedford Avenue, Brooklyn, New York 11210, United States
- Ph.D.
Program in Chemistry, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, New York 10016, United States
| | - Alexander Greer
- Department
of Chemistry, Brooklyn College, 2900 Bedford Avenue, Brooklyn, New York 11210, United States
- Ph.D.
Program in Chemistry, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, New York 10016, United States
| |
Collapse
|
5
|
Williams YD, Meck C, Mohd N, Murelli RP. Triflic acid-mediated rearrangements of 3-methoxy-8-oxabicyclo[3.2.1]octa-3,6-dien-2-ones: synthesis of methoxytropolones and furans. J Org Chem 2013; 78:11707-13. [PMID: 24171600 PMCID: PMC3909939 DOI: 10.1021/jo401617r] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Methoxytropolones are useful scaffolds for therapeutic development because of their known biological activity and established value in the synthesis of α-hydroxytropolones. Upon treatment with triflic acid, a series of 3-methoxy-8-oxabicyclo[3.2.1]octa-3,6-dien-2-ones rearrange rapidly and cleanly to form methoxytropolones. Interestingly, bicycles that are derived from dimethyl acetylenedicarboxylate (R(2) = R(3) = CO2Me) instead form furans as the major product.
Collapse
Affiliation(s)
- Yvonne D. Williams
- Department of Chemistry, Brooklyn College, The City University of New York, 2900 Bed-ford Avenue, Brooklyn College, Brooklyn, New York, 11210, United StatesDepartment of Chemistry, The Graduate Center, The City University of New York, 365 Fifth Avenue, New York, NY 10016, United States
| | - Christine Meck
- Department of Chemistry, Brooklyn College, The City University of New York, 2900 Bed-ford Avenue, Brooklyn College, Brooklyn, New York, 11210, United StatesDepartment of Chemistry, The Graduate Center, The City University of New York, 365 Fifth Avenue, New York, NY 10016, United States
| | - Noushad Mohd
- Department of Chemistry, Brooklyn College, The City University of New York, 2900 Bed-ford Avenue, Brooklyn College, Brooklyn, New York, 11210, United StatesDepartment of Chemistry, The Graduate Center, The City University of New York, 365 Fifth Avenue, New York, NY 10016, United States
| | - Ryan P. Murelli
- Department of Chemistry, Brooklyn College, The City University of New York, 2900 Bed-ford Avenue, Brooklyn College, Brooklyn, New York, 11210, United StatesDepartment of Chemistry, The Graduate Center, The City University of New York, 365 Fifth Avenue, New York, NY 10016, United States
| |
Collapse
|
6
|
Catak S, Celik H, Demir AS, Aviyente V. Origin of Diastereoselectivity in the Synthesis of Chiral Bicyclic Lactams: π-Facial Selective Attack of Singlet Oxygen Induced by Hindered Internal Rotation. J Phys Chem A 2007; 111:5855-63. [PMID: 17566992 DOI: 10.1021/jp071608y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Previously reported experimental results indicate that photooxygenation of homochiral N-(hydroxyalkyl)-2-methylpyrroles with singlet oxygen yields trans-rather than cis-bicyclic lactams as the major product. In this study, the origin of selectivity in this reaction has been investigated with computational methods. Relative stabilities of homochiral N-(hydroxyalkyl)-2-methylpyrrole conformers and their effect on pi-facial selectivity of 1O2 were extensively studied. Stepwise and concerted reaction mechanisms, starting from the endoperoxide intermediates, were proposed and modeled in vacuum using the UB3LYP method with the 6-31+G** basis set. Solvent calculations were carried out in CH2Cl2, by means of the integral equation formalism-polarizable continuum model (IEF-PCM) at the UB3LYP/6-31+G** level of theory. Free energies of activation leading to both diastereomers were analyzed in an effort to explain the stereoselectivity and product distribution. Steric interactions among the pyrrole substituents were shown to lead to a rotational barrier higher than 10 kcal/mol. Hence, hindered internal rotation is suggested to cause one pyrrole conformer to be substantially overpopulated. This in turn has a major effect on pi-facial selectivity of 1O2, thereby favoring one endoperoxide over the other and leading to the diastereoselective synthesis of trans-pyrrolooxazolones. The importance of hindered internal rotors, for an accurate calculation of the frequency factors of a chemical reaction, has already been mentioned in the literature many times; however, in this work hindered internal rotors also seem to dictate the diastereoselective outcome of the reaction.
Collapse
Affiliation(s)
- Saron Catak
- Department of Chemistry, Bogazici University, 34342 Bebek, Istanbul, Turkey
| | | | | | | |
Collapse
|
7
|
Pavlov VY. Modern aspects of the Chemistry of protoporphyrin IX. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2007. [DOI: 10.1134/s1070428007010010] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
8
|
|
9
|
Güney M, Daştan A, Balci M. Chemistry of the Benzotropone Endoperoxides and Their Conversion into Tropolone Derivatives: Unusual Endoperoxide Rearrangements. Helv Chim Acta 2005. [DOI: 10.1002/hlca.200590061] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
10
|
Abstract
This review covers beta-phenylethylamines and isoquinoline alkaloids and compounds derived from them, including further products of oxidation, condensation with formaldehyde and rearrangement, some of which do not contain an isoquinoline system, together with naphthylisoquinoline alkaloids, which have a different biogenetic origin. The occurrence of the alkaloids, with the structures of new bases, together with their reactions, syntheses and biological activities are reported. The literature from July 2001 to June 2002 is reviewed, with 581 references cited.
Collapse
|