1
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Sun W, Wilding-Steele L, Brown RCD, Harrowven DC. Aryl-aryl cross-coupling reactions without reagents or catalysts: photocyclization of ortho-iodoaryl ethers and related compounds via triplet aryl cation intermediates. Chem Commun (Camb) 2023; 59:10797-10800. [PMID: 37594190 DOI: 10.1039/d3cc03271j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/19/2023]
Abstract
Cyclisations of benzyl ortho-iodoaryl ethers to benzo[c]chromenes can be effected without reagents or catalysts by irradiation with UVC under flow. Reactions proceed via triplet aryl cation generation, 5-exo and 3-exo-cyclisations, and rearomatisation. They have wide scope, are easy to effect and extend to a myriad of related ring systems.
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Affiliation(s)
- Wei Sun
- Department of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK.
| | - Luke Wilding-Steele
- Department of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK.
| | - Richard C D Brown
- Department of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK.
| | - David C Harrowven
- Department of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK.
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2
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Kao MH, Orr-Ewing AJ. Charge-Separated Reactive Intermediates from the UV Photodissociation of Chlorobenzene in Solution. J Phys Chem A 2022; 126:6934-6943. [PMID: 36148486 PMCID: PMC9549464 DOI: 10.1021/acs.jpca.2c05327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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Although ultraviolet
(UV)-induced photochemical cleavage of carbon–halogen
bonds in gaseous halocarbons is mostly homolytic, the photolysis of
chlorobenzene in solution has been proposed to produce a phenyl cation,
c-C6H5+, which is a highly reactive
intermediate of potential use in chemical synthesis and N2 activation. Any evidence for such a route to phenyl cations is indirect,
with uncertainty remaining about the possible mechanism. Here, ultrafast
transient absorption spectroscopy of UV-excited (λ = 240 and
270 nm) chlorobenzene solutions in fluorinated (perfluorohexane) and
protic (ethanol and 2,2,2-trifluoroethanol) solvents reveals a broad
electronic absorption band centered at 540 nm that is assigned to
an isomer of chlorobenzene with both charge-separated and triplet-spin
carbene character. This spectroscopic feature is weaker, or absent,
when experiments are conducted in cyclohexane. The intermediate isomer
of chlorobenzene has a solvent-dependent lifetime of 30–110
ps, determined by reaction with the solvent or quenching to a lower-lying
singlet state. Evidence is presented for dissociation to ortho-benzyne, but the intermediate could also be a precursor to phenyl
cation formation.
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Affiliation(s)
- Min-Hsien Kao
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Andrew J Orr-Ewing
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
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3
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Borisov YA, Akhrem IS. DFT evidence for hydride transfer from aromatic C H bond to superelectrophile in reactions of 1,3,5-Ad3C6H3 with CBr3+ Al2Br7− and 1,3,5-Ad3C6H3 with CBr3+ Al2Br7− and CO. MOLECULAR CATALYSIS 2020. [DOI: 10.1016/j.mcat.2017.09.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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4
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Kaur N, Bhardwaj P, Devi M, Verma Y, Grewal P. Photochemical reactions in five and six-membered polyheterocycles synthesis. SYNTHETIC COMMUN 2019. [DOI: 10.1080/00397911.2019.1622732] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Navjeet Kaur
- Department of Chemistry, Banasthali Vidyapith, Banasthali, India
| | - Pranshu Bhardwaj
- Department of Chemistry, Banasthali Vidyapith, Banasthali, India
| | - Meenu Devi
- Department of Chemistry, Banasthali Vidyapith, Banasthali, India
| | - Yamini Verma
- Department of Chemistry, Banasthali Vidyapith, Banasthali, India
| | - Pooja Grewal
- Department of Chemistry, Banasthali Vidyapith, Banasthali, India
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5
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DFT B3LYP/6-311+G* calculation study of a new nonclassical mechanism of electrophilic functionalization of aromatic C–H bond via aryl cation formation. MENDELEEV COMMUNICATIONS 2019. [DOI: 10.1016/j.mencom.2019.05.035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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6
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Pedroli C, Ravelli D, Protti S, Albini A, Fagnoni M. Singlet vs Triplet Reactivity of Photogenerated α,n-Didehydrotoluenes. J Org Chem 2017; 82:6592-6603. [DOI: 10.1021/acs.joc.7b00610] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Chiara Pedroli
- Department of Chemistry, PhotoGreen Lab, Viale
Taramelli 12, 27100 Pavia, Italy
| | - Davide Ravelli
- Department of Chemistry, PhotoGreen Lab, Viale
Taramelli 12, 27100 Pavia, Italy
| | - Stefano Protti
- Department of Chemistry, PhotoGreen Lab, Viale
Taramelli 12, 27100 Pavia, Italy
| | - Angelo Albini
- Department of Chemistry, PhotoGreen Lab, Viale
Taramelli 12, 27100 Pavia, Italy
| | - Maurizio Fagnoni
- Department of Chemistry, PhotoGreen Lab, Viale
Taramelli 12, 27100 Pavia, Italy
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7
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8
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Zhu R, Li MD, Du L, Phillips DL. Singlet versus Triplet Excited State Mediated Photoinduced Dehalogenation Reactions of Itraconazole in Acetonitrile and Aqueous Solutions. J Phys Chem B 2017; 121:2712-2720. [PMID: 28281345 DOI: 10.1021/acs.jpcb.6b11934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Photoinduced dehalogenation of the antifungal drug itraconazole (ITR) in acetonitrile (ACN) and ACN/water mixed solutions was investigated using femtosecond and nanosecond time-resolved transient absorption (fs-TA and ns-TA, respectively) and nanosecond time-resolved resonance Raman spectroscopy (ns-TR3) experiments. An excited resonance energy transfer is found to take place from the 4-phenyl-4,5-dihydro-3H-1,2,4-triazol-3-one part of the molecule to the 1,3-dichlorobenzene part of the molecule when ITR is excited by ultraviolet light. This photoexcitation is followed by a fast carbon-halogen bond cleavage that leads to the generation of radical intermediates via either triplet and/or singlet excited states. It is found that the singlet excited state-mediated carbon-halogen cleavage is the predominant dehalogenation process in ACN solvent, whereas a triplet state-mediated carbon-halogen cleavage prefers to occur in the ACN/water mixed solutions. The singlet-to-triplet energy gap is decreased in the ACN/water mixed solvents and this helps facilitate an intersystem crossing process, and thus, the carbon-halogen bond cleavage happens mostly through an excited triplet state in the aqueous solutions examined. The ns-TA and ns-TR3 results also provide some evidence that radical intermediates are generated through a homolytic carbon-halogen bond cleavage via predominantly the singlet excited state pathway in ACN but via mainly the triplet state pathway in the aqueous solutions. In strong acidic solutions, protonation at the oxygen and/or nitrogen atoms of the 1,2,4-triazole-3-one group appears to hinder the dehalogenation reactions. This may offer the possibility that the phototoxicity of ITR due to the generation of aryl or halogen radicals can be reduced by protonation of certain moieties in suitably designed ITR halogen-containing derivatives.
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Affiliation(s)
- Ruixue Zhu
- Department of Chemistry, The University of Hong Kong , Pokfulam Road, Pokfulam, Hong Kong S.A.R., P. R. China
| | - Ming-de Li
- Department of Chemistry, The University of Hong Kong , Pokfulam Road, Pokfulam, Hong Kong S.A.R., P. R. China.,Department of Chemistry, Shantou University , Shantou 515063, China
| | - Lili Du
- Department of Chemistry, The University of Hong Kong , Pokfulam Road, Pokfulam, Hong Kong S.A.R., P. R. China
| | - David Lee Phillips
- Department of Chemistry, The University of Hong Kong , Pokfulam Road, Pokfulam, Hong Kong S.A.R., P. R. China
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9
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Raviola C, Chiesa F, Protti S, Albini A, Fagnoni M. On the Route to the Photogeneration of Heteroaryl Cations. The Case of Halothiophenes. J Org Chem 2016; 81:6336-42. [PMID: 27383725 DOI: 10.1021/acs.joc.6b00978] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
2-Chloro-, 2-bromo-, and 2-iodothiophenes undergo photochemical dehalogenation via the triplet state. In the presence of suitable π-bond nucleophiles, thienylation occurs with modest yield from chloro and bromo derivatives (via photogenerated triplet 2-thienyl cation). Specific trapping by using oxygen along with computational analysis carried out by means of a density functional method support that, in the case of iodo derivatives, homolytic thienyl-I bond fragmentation occurs first and heteroaryl cations are formed by electron transfer within the triplet radical pair, thus opening an indirect access to such cations.
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Affiliation(s)
- Carlotta Raviola
- PhotoGreen Lab, Department of Chemistry, University of Pavia , Viale Taramelli 12, 27100 Pavia, Italy
| | - Francesco Chiesa
- Department of Chemistry, University of Pavia , Viale Taramelli 12, 27100 Pavia, Italy
| | - Stefano Protti
- PhotoGreen Lab, Department of Chemistry, University of Pavia , Viale Taramelli 12, 27100 Pavia, Italy
| | - Angelo Albini
- PhotoGreen Lab, Department of Chemistry, University of Pavia , Viale Taramelli 12, 27100 Pavia, Italy
| | - Maurizio Fagnoni
- PhotoGreen Lab, Department of Chemistry, University of Pavia , Viale Taramelli 12, 27100 Pavia, Italy
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10
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Rayne S, Forest K. Singlet–triplet excitation energies of substituted phenyl cations: a G4(MP2) and G4 theoretical study. Theor Chem Acc 2016. [DOI: 10.1007/s00214-016-1837-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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11
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Bondarchuk SV, Minaev BF. Thermally accessible triplet state of π-nucleophiles does exist. Evidence from first principles study of ethylene interaction with copper species. RSC Adv 2015. [DOI: 10.1039/c4ra12422g] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Three different models of ethylene interaction with copper species, namely, the Cu(100) surface, odd-numbered copper clusters C2H4/Cun (where n = 3, 7, 11, 15, 17, 19, 21, 25 and 27) and atomic copper C2H4/Cu were studied theoretically.
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Affiliation(s)
- Sergey V. Bondarchuk
- Department of Organic Chemistry
- Bogdan Khmelnitsky Cherkasy National University
- 18031 Cherkasy
- Ukraine
| | - Boris F. Minaev
- Department of Organic Chemistry
- Bogdan Khmelnitsky Cherkasy National University
- 18031 Cherkasy
- Ukraine
- Department of Theoretical Chemistry and Biochemistry
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12
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Crespi S, Ravelli D, Protti S, Albini A, Fagnoni M. Competing pathways in the photogeneration of didehydrotoluenes from (Trimethylsilylmethyl)aryl sulfonates and phosphates. Chemistry 2014; 20:17572-8. [PMID: 25358804 DOI: 10.1002/chem.201404787] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Indexed: 11/11/2022]
Abstract
The scope of the photochemical generation of α,n-didehydrotoluene diradicals from aryl sulfonates and phosphates and their chemistry are explored. The thermally inaccessible α,2- and α,4- intermediates are efficiently obtained by irradiation of ortho- and para-(trimethylsilylmethyl)phenyl triflates through heterolytic splitting of the ester anion from the substrate in the triplet state. Triplet phenyl cations are formed and the loss of trimethylsilyl cation from them affords the desired diradicals ((3) Me3 SiCH2 C6 H4 -OZ→(3) Me3 SiCH2 C6 H4 (+) →(⋅) CH2 C6 H4 (⋅)). Triplet sensitization is required, for which acetone is used throughout. Direct irradiation leads, on the contrary, to photo-Fries fragmentation ((1) Me3 SiCH2 C6 H4 O-Z→Me3 SiCH2 C6 H4 O(⋅) +Z(⋅)). With mesylates, where ester cleavage is less convenient, a further competition from the triplet is direct desilylation. Didehydrotoluenes are also obtained from the corresponding phosphates, although with poor efficiency.
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Affiliation(s)
- Stefano Crespi
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia (Italy)
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13
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Raviola C, Ravelli D, Protti S, Fagnoni M. Methoxy-Substituted α,n-Didehydrotoluenes. Photochemical Generation and Polar vs Diradical Reactivity. J Am Chem Soc 2014; 136:13874-81. [DOI: 10.1021/ja507735u] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Carlotta Raviola
- Photogreen
Lab, Department
of Chemistry, University of Pavia, V. Le Taramelli 12, 27100 Pavia, Italy
| | - Davide Ravelli
- Photogreen
Lab, Department
of Chemistry, University of Pavia, V. Le Taramelli 12, 27100 Pavia, Italy
| | - Stefano Protti
- Photogreen
Lab, Department
of Chemistry, University of Pavia, V. Le Taramelli 12, 27100 Pavia, Italy
| | - Maurizio Fagnoni
- Photogreen
Lab, Department
of Chemistry, University of Pavia, V. Le Taramelli 12, 27100 Pavia, Italy
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14
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The singlet–triplet energy splitting of π-nucleophiles as a measure of their reaction rate with electrophilic partners. Chem Phys Lett 2014. [DOI: 10.1016/j.cplett.2014.05.040] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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15
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Bondarchuk SV, Minaev BF. State-Dependent Global and Local Electrophilicity of the Aryl Cations. J Phys Chem A 2014; 118:3201-10. [DOI: 10.1021/jp501740p] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Sergey V. Bondarchuk
- Department
of Organic Chemistry, Bogdan Khmelnitsky Cherkasy National University, Boulevard Shevchenko 81, 18031 Cherkasy, Ukraine
| | - Boris F. Minaev
- Department
of Organic Chemistry, Bogdan Khmelnitsky Cherkasy National University, Boulevard Shevchenko 81, 18031 Cherkasy, Ukraine
- Department
of Chemistry, Tomsk State University, Prospekt Lenina 36, 634050 Tomsk, Russian Federation
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16
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Perrotta RR, Falvey DE. The 3,5-dinitroanilide anion: a singlet anilide anion with evidence for a thermally accessible triplet state. J PHYS ORG CHEM 2013. [DOI: 10.1002/poc.3118] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Raffaele R. Perrotta
- Department of Chemistry and Biochemistry; University of Maryland; College Park MD 20740-2012 USA
| | - Daniel E. Falvey
- Department of Chemistry and Biochemistry; University of Maryland; College Park MD 20740-2012 USA
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17
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Qrareya H, Raviola C, Protti S, Fagnoni M, Albini A. Transition-Metal-Free Arylations via Photogenerated Triplet 4-Alkyl- and 4-Trimethylsilylphenyl Cations. J Org Chem 2013; 78:6016-24. [DOI: 10.1021/jo4007046] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hisham Qrareya
- PhotoGreen Lab, Department of Chemistry, University of Pavia, V. Le Taramelli 12, 27100 Pavia,
Italy
| | - Carlotta Raviola
- PhotoGreen Lab, Department of Chemistry, University of Pavia, V. Le Taramelli 12, 27100 Pavia,
Italy
| | - Stefano Protti
- PhotoGreen Lab, Department of Chemistry, University of Pavia, V. Le Taramelli 12, 27100 Pavia,
Italy
| | - Maurizio Fagnoni
- PhotoGreen Lab, Department of Chemistry, University of Pavia, V. Le Taramelli 12, 27100 Pavia,
Italy
| | - Angelo Albini
- PhotoGreen Lab, Department of Chemistry, University of Pavia, V. Le Taramelli 12, 27100 Pavia,
Italy
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18
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Protti S, Ravelli D, Fagnoni M, Albini A. Smooth photogeneration of α,n-didehydrotoluenes (DHTs). PURE APPL CHEM 2013. [DOI: 10.1351/pac-con-12-10-03] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Irradiation of the three isomeric (chlorobenzyl)trimethylsilanes in
methanol–water generates the corresponding didehydrotoluenes (DHTs). The process
involves expulsion of a chloride ion to give the triplet phenyl cation and
ensuing elimination of the trimethylsilyl cation. This straightforward
generation of DHT intermediates overcomes a shortcoming of previous methodology
(cycloaromatization of enyne-allenes), which is limited to the
meta-isomer, and opens the path for understanding the
chemistry (and possibly the biological action) of these unusual
intermediates.
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Affiliation(s)
- Stefano Protti
- 1PhotoGreen Lab, Department of Chemistry, University of Pavia, via Taramelli 12, 27100 Pavia, Italy
| | - Davide Ravelli
- 1PhotoGreen Lab, Department of Chemistry, University of Pavia, via Taramelli 12, 27100 Pavia, Italy
| | - Maurizio Fagnoni
- 1PhotoGreen Lab, Department of Chemistry, University of Pavia, via Taramelli 12, 27100 Pavia, Italy
| | - Angelo Albini
- 1PhotoGreen Lab, Department of Chemistry, University of Pavia, via Taramelli 12, 27100 Pavia, Italy
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19
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Ravelli D, Protti S, Fagnoni M, Albini A. From Phenyl Chlorides to α,n-Didehydrotoluenes via Phenyl Cations. A CPCM–CASMP2 Investigation. J Org Chem 2013; 78:3814-20. [DOI: 10.1021/jo400269s] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Davide Ravelli
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia,
Italy
| | - Stefano Protti
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia,
Italy
| | - Maurizio Fagnoni
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia,
Italy
| | - Angelo Albini
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia,
Italy
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20
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Hoffmann N. Photochemical reactions of aromatic compounds and the concept of the photon as a traceless reagent. Photochem Photobiol Sci 2013; 11:1613-41. [PMID: 22732723 DOI: 10.1039/c2pp25074h] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Electronic excitation significantly changes the reactivity of chemical compounds. Compared to ground state reactions, photochemical reactions considerably enlarge the application spectrum of a particular functional group in organic synthesis. Multistep syntheses may be simplified and perspectives for target oriented synthesis (TOS) and diversity oriented synthesis (DOS) are developed. New compound families become available or may be obtained more easily. In contrast to common chemical reagents, photons don't generate side products resulting from the transformation of a chemical reagent. Therefore, they are considered as a traceless reagent. Consequently, photochemical reactions play a central role in the methodology of sustainable chemistry. This aspect has been recognized since the beginning of the 20th century. As with many other photochemical transformations, photochemical reactions of aromatic, benzene-like compounds illustrate well the advantages in this context. Photochemical cycloadditions of aromatic compounds have been investigated for a long time. Currently, they are applied in various fields of organic synthesis. They are also studied in supramolecular structures. The phenomena of reactivity and stereoselectivity are investigated. During recent years, photochemical electron transfer mediated reactions are particularly focused. Such transformations have likewise been performed with aromatic compounds. Reactivity and selectivity as well as application to organic synthesis are studied.
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Affiliation(s)
- Norbert Hoffmann
- Institut de Chimie Moléculaire de Reims, UMR 7312 CNRS et Université de Reims Champagne-Ardenne, Equipe de Photochimie, UFR Sciences, B.P. 1039, F-51687 Reims, cedex 02, France.
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21
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Raviola C, Protti S, Ravelli D, Mella M, Albini A, Fagnoni M. Acetalization allows the photoheterolysis of the Ar-Cl bond in chlorobenzaldehydes and chloroacetophenones. J Org Chem 2012; 77:9094-101. [PMID: 22963457 DOI: 10.1021/jo3016264] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The nonaccessibility of phenyl cations by irradiation of electron-poor aryl chlorides was circumvented by transforming the carbonyl group of aromatic ketones or aldehydes into the corresponding 1,3-dioxolanes and the carboxyl group of benzoate ester into an orthoester functionality. This transformation allowed the heterolytic photoactivation of the Ar-Cl bond in protic media and the generation of phenyl cations. In the presence of π-bond nucleophiles, arylated products were obtained in good to excellent yields.
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Affiliation(s)
- Carlotta Raviola
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
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22
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Abitelli E, Protti S, Fagnoni M, Albini A. Probing for a Leaving Group Effect on the Generation and Reactivity of Phenyl Cations. J Org Chem 2012; 77:3501-7. [DOI: 10.1021/jo300290v] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Erika Abitelli
- PhotoGreenLab,
Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia,
Italy
| | - Stefano Protti
- PhotoGreenLab,
Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia,
Italy
| | - Maurizio Fagnoni
- PhotoGreenLab,
Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia,
Italy
| | - Angelo Albini
- PhotoGreenLab,
Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia,
Italy
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