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Jorea A, Raviola C, Giustiniano M, Ravelli D. Decatungstate‐photocatalyzed functionalization of α‐imino esters for the preparation of unnatural α‐amino acid derivatives. ChemCatChem 2023. [DOI: 10.1002/cctc.202300042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Affiliation(s)
- Alexandra Jorea
- University of Pavia: Universita degli Studi di Pavia Department of Chemistry ITALY
| | - Carlotta Raviola
- University of Pavia: Universita degli Studi di Pavia Department of Chemistry ITALY
| | - Mariateresa Giustiniano
- University of Naples Federico II: Universita degli Studi di Napoli Federico II Department of Pharmacy ITALY
| | - Davide Ravelli
- University of Pavia: Universita degli Studi di Pavia Department of Chemistry viale Taramelli 12 27100 Pavia ITALY
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2
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Di Terlizzi L, Scaringi S, Raviola C, Pedrazzani R, Bandini M, Fagnoni M, Protti S. Visible Light-Driven, Gold(I)-Catalyzed Preparation of Symmetrical (Hetero)biaryls by Homocoupling of Arylazo Sulfones. J Org Chem 2022; 87:4863-4872. [PMID: 35316603 PMCID: PMC8981317 DOI: 10.1021/acs.joc.2c00225] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
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The preparation of
symmetrical (hetero)biaryls via arylazo sulfones
has been successfully carried out upon visible light irradiation in
the presence of PPh3AuCl as the catalyst. The present protocol
led to the efficient synthesis of a wide range of target compounds
in an organic-aqueous solvent under photocatalyst-free conditions.
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Affiliation(s)
- Lorenzo Di Terlizzi
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Simone Scaringi
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy.,Department of Organic Chemistry, University of Geneva, 30 quai Ernest Ansermet, 1211 Geneva, Switzerland
| | - Carlotta Raviola
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Riccardo Pedrazzani
- Dipartimento di Chimica ″Giacomo Ciamician″, Alma Mater Studiorum-University of Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Marco Bandini
- Dipartimento di Chimica ″Giacomo Ciamician″, Alma Mater Studiorum-University of Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Maurizio Fagnoni
- 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
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3
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Raviola C, Carrera C, Serra M, Palmieri A, Lupidi G, Maestri G, Protti S. Visible‐Light‐Driven Competitive Stereo‐ and Regioisomerization of (
E
)‐β‐Nitroenones. CHEMPHOTOCHEM 2021. [DOI: 10.1002/cptc.202100081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Carlotta Raviola
- PhotoGreen Lab Department of Chemistry University of Pavia Viale Taramelli 10 27100 Pavia Italy
| | - Cristina Carrera
- PhotoGreen Lab Department of Chemistry University of Pavia Viale Taramelli 10 27100 Pavia Italy
- Department of Drug Sciences University of Pavia Viale Taramelli 12 27100 Pavia Italy
| | - Massimo Serra
- Department of Drug Sciences University of Pavia Viale Taramelli 12 27100 Pavia Italy
| | - Alessandro Palmieri
- Green Chemistry Group -School of Science and Technology Chemistry Division University of Camerino Via S. Agostino 1 62032 Camerino Italy
| | - Gabriele Lupidi
- Green Chemistry Group -School of Science and Technology Chemistry Division University of Camerino Via S. Agostino 1 62032 Camerino Italy
| | - Giovanni Maestri
- Department of Chemistry, Life Sciences and Environmental Sustainability University of Parma Parco Area delle Scienze 17/A 43124 Parma Italy
| | - Stefano Protti
- PhotoGreen Lab Department of Chemistry University of Pavia Viale Taramelli 10 27100 Pavia Italy
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4
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Abstract
The synthesis of α-arylketones and α-arylazo esters has been achieved in mixed organic-aqueous media under photocatalyst- and metal-free conditions via visible light activation of arylazo sulfones in the presence of enol silyl ethers and ketene silyl acetals, respectively. The process took place efficiently and exhibits an excellent tolerance for a broad variety of functional groups.
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5
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Affiliation(s)
- Carlotta Raviola
- PhotoGreen Lab University of Pavia Viale Taramelli 10 27100 Pavia Italy
| | - Stefano Protti
- PhotoGreen Lab University of Pavia Viale Taramelli 10 27100 Pavia Italy
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6
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Emanuele A, Cailotto S, Campalani C, Branzi L, Raviola C, Ravelli D, Cattaruzza E, Trave E, Benedetti A, Selva M, Perosa A. Precursor-Dependent Photocatalytic Activity of Carbon Dots. Molecules 2019; 25:E101. [PMID: 31888094 PMCID: PMC6983025 DOI: 10.3390/molecules25010101] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 12/22/2019] [Accepted: 12/24/2019] [Indexed: 11/17/2022] Open
Abstract
This work systematically compares both structural features and photocatalytic performance of a series of graphitic and amorphous carbon dots (CDs) prepared in a bottom-up manner from fructose, glucose, and citric acid. We demonstrate that the carbon source and synthetic procedures diversely affect the structural and optical properties of the CDs, which in turn unpredictably influence their photo electron transfer ability. The latter was evaluated by studying the photo-reduction of methyl viologen. Overall, citric acid-CDs were found to provide the best photocatalytic performance followed by fructose- and glucose-CDs. However, while the graphitization of glucose- and citric acid-CDs favored the photo-reaction, a reverse structure-activity dependence was observed for fructose-CDs due to the formation of a large graphitic-like supramolecular assembly. This study highlights the complexity to design in advance photo-active bio-based carbon nanomaterials.
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Affiliation(s)
- Amadio Emanuele
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venezia Mestre, Italy; (S.C.); (C.C.); (L.B.); (E.C.); (E.T.); (A.B.); (M.S.); (A.P.)
| | - Simone Cailotto
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venezia Mestre, Italy; (S.C.); (C.C.); (L.B.); (E.C.); (E.T.); (A.B.); (M.S.); (A.P.)
| | - Carlotta Campalani
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venezia Mestre, Italy; (S.C.); (C.C.); (L.B.); (E.C.); (E.T.); (A.B.); (M.S.); (A.P.)
| | - Lorenzo Branzi
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venezia Mestre, Italy; (S.C.); (C.C.); (L.B.); (E.C.); (E.T.); (A.B.); (M.S.); (A.P.)
| | - Carlotta Raviola
- PhotoGreen Lab, Department of Chemistry, University of Pavia, 27100 Pavia, Italy; (C.R.); (D.R.)
| | - Davide Ravelli
- PhotoGreen Lab, Department of Chemistry, University of Pavia, 27100 Pavia, Italy; (C.R.); (D.R.)
| | - Elti Cattaruzza
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venezia Mestre, Italy; (S.C.); (C.C.); (L.B.); (E.C.); (E.T.); (A.B.); (M.S.); (A.P.)
| | - Enrico Trave
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venezia Mestre, Italy; (S.C.); (C.C.); (L.B.); (E.C.); (E.T.); (A.B.); (M.S.); (A.P.)
| | - Alvise Benedetti
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venezia Mestre, Italy; (S.C.); (C.C.); (L.B.); (E.C.); (E.T.); (A.B.); (M.S.); (A.P.)
| | - Maurizio Selva
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venezia Mestre, Italy; (S.C.); (C.C.); (L.B.); (E.C.); (E.T.); (A.B.); (M.S.); (A.P.)
| | - Alvise Perosa
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venezia Mestre, Italy; (S.C.); (C.C.); (L.B.); (E.C.); (E.T.); (A.B.); (M.S.); (A.P.)
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7
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Abdulla HO, Amin AA, Raviola C, Opatz T, Protti S, Fagnoni M. Smooth Metal-Free Photoinduced Preparation of Valuable 8-Arylxanthines. European J Org Chem 2019. [DOI: 10.1002/ejoc.201900638] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Havall Othman Abdulla
- PhotoGreen Lab; Department of Chemistry; University of Pavia; Viale Taramelli 12 27100 Pavia Italy
- Chemistry Department; College of Science; Salahaddin University; Erbil Iraq
| | - Ahmed A. Amin
- Chemistry Department; College of Education; Salahaddin University; Erbil Iraq
| | - Carlotta Raviola
- PhotoGreen Lab; Department of Chemistry; University of Pavia; Viale Taramelli 12 27100 Pavia Italy
| | - Till Opatz
- Institute of Organic Chemistry; College of Education; Johannes Gutenberg University of Mainz; 55128 Mainz Germany
| | - 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
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8
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Amin HIM, Raviola C, Amin AA, Mannucci B, Protti S, Fagnoni M. Hydro/Deutero Deamination of Arylazo Sulfones under Metal- and (Photo)Catalyst-Free Conditions. Molecules 2019; 24:E2164. [PMID: 31181774 PMCID: PMC6601019 DOI: 10.3390/molecules24112164] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 06/03/2019] [Accepted: 06/05/2019] [Indexed: 11/17/2022] Open
Abstract
Hydrodeaminated and monodeuterated aromatics were obtained via a visible-light driven reaction of arylazo sulfones. Deuteration occurs efficiently in deuterated media such as isopropanol-d8 or in THF-d8/water mixtures and exhibits a high tolerance to the nature and the position of the aromatic substituents.
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Affiliation(s)
- Hawraz I M Amin
- PhotoGreen Lab, Department of Chemistry, University of Pavia. Viale Taramelli 12, 27100 Pavia, Italy.
- Chemistry Department, College of Science, Salahaddin University-Erbil, Erbil 44001, Iraq.
| | - Carlotta Raviola
- PhotoGreen Lab, Department of Chemistry, University of Pavia. Viale Taramelli 12, 27100 Pavia, Italy.
| | - Ahmed A Amin
- Chemistry Department, College of Education, Salahaddin University-Erbil, Erbil 44001, Iraq.
| | - Barbara Mannucci
- Centro Grandi Strumenti (CGS), University of Pavia, V. Bassi 21, 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.
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9
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Raviola C, Ravelli D. Efficiency and Selectivity Aspects in the C–H Functionalization of Aliphatic Oxygen Heterocycles by Photocatalytic Hydrogen Atom Transfer. Synlett 2019. [DOI: 10.1055/s-0037-1612079] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The C–H to C–C conversion in aliphatic oxygen heterocycles (dioxolanes, 1,3-dioxane, or cyclic carbonates) by photocatalytic hydrogen atom transfer and subsequent trapping of the resulting radical with phenyl vinyl sulfone was investigated. The performance of three different photocatalysts, namely tetrabutylammonium decatungstate and the aromatic ketones thioxanthone and 9-fluorenone, was compared. The UV-light-absorbing decatungstate anion is more efficient and permits the use of a smaller excess of hydrogen donor than the aromatic ketones, although the ketones could be excited by visible light. Further intramolecular selectivity studies revealed that aromatic ketones afforded a higher proportion of functionalization at the acetalic versus the ethereal positions than did the decatungstate anion.
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Affiliation(s)
| | - Davide Ravelli
- PhotoGreen Laboratory, Department of Chemistry, University of Pavia
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10
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Onuigbo L, Raviola C, Di Fonzo A, Protti S, Fagnoni M. Sunlight-Driven Synthesis of Triarylethylenes (TAEs) via Metal-Free Mizoroki-Heck-Type Coupling. European J Org Chem 2018. [DOI: 10.1002/ejoc.201800883] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Louis Onuigbo
- 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
| | - Andrea Di Fonzo
- Laboratorio Biochimica; Biotecnologie e Diagnostica Avanzata; Fondazione IRCCS Policlinico San Matteo; 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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11
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Raviola C, Fagnoni M. Search for a photoinduced (site-selective) cleavage of the Ar-Cl bond in dichloroanisoles. Photochem Photobiol Sci 2018; 17:107-117. [PMID: 29239452 DOI: 10.1039/c7pp00372b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The site-selective cleavage of an Ar-X bond in polyhalogenated aromatics is an important tool in synthetic planning especially when more than one identical halogen atom is present. An alternative to the usual metal-catalyzed cleavage is represented by photochemistry although only a few examples have been reported. We then investigated the feasibility of the site-selective photodechlorination of some dichloroanisoles through a combined experimental and computational study. In the case of 2,4-dichloroanisole, selective detachment of the chlorine atom at the ortho position with respect to the OMe group was observed upon photohomolysis (in cyclohexane) or photoheterolysis (in MeOH) of the Ar-Cl bond. In the latter case, 5-chloro-2-methoxy-1,1'-biphenyl was exclusively formed upon reaction of the resulting phenyl cation with benzene. The substitution of an OH group for a OMe group was detrimental since a lower photoreactivity resulted with no improvement in the selectivity.
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Affiliation(s)
- Carlotta Raviola
- PhotoGreen Lab, Department of Chemistry, V. Le Taramelli 12, 27100 Pavia, Italy.
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12
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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13
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Abstract
Recent advances in the synthesis of (hetero)aromatics starting from polyenes, such as dienynes, enediynes and enyne–allenes, are discussed.
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14
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Raviola C, Ravelli D, Protti S, Albini A, Fagnoni M. Conditions and Edges for the Photochemical Generation of Short-Lived Aryl Cations: A Computational Approach. Synlett 2015. [DOI: 10.1055/s-0034-1379945] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
A DFT investigation on the conditions required for the photochemical generation of triplet aryl cations from differently para-substituted aryl halides has been carried out. The results showed a correlation between the energy change associated with the Ar–X bond heterolytic cleavage and the substituent Hammett–Brown constant (σp
+). The method provides a means to predict the viability of the ArSN1 photosubstitution reaction.
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15
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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16
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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17
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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18
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Ryan SV, Dougherty MJ, Chang M, Lombardi J, Raviola C, Calligaro K. Abnormal duplex findings at the proximal anastomosis of infrainguinal bypass grafts: does revision enhance patency? Ann Vasc Surg 2001; 15:98-103. [PMID: 11221953 DOI: 10.1007/s100160010004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Using color duplex ultrasound (CDU) surveillance of autogenous infrainguinal bypasses, a peak systolic flow velocity (PSFV) ratio of greater than 3 to 1 within the graft relative to adjacent PSFV has been accepted as predicting significant stenosis mandating revision. At the proximal anastomosis, where significant vessel diameter differences and turbulent flow exist, the validity of these criteria is less clear. Our purpose was to review our experience with proximal anastomotic abnormalities in a CDU surveillance protocol. Routine CDU surveillance for all infrainguinal bypass gratis consisted of evaluation in an accredited vascular laboratory at 1 month postoperatively, every 3 months for the first year, every 6 months in the second year, and annually thereafter. Grafts with a PSFV ratio of >3 at the proximal anastomosis on any CDU study were included in this review. From our results we conclude that currently accepted CDU criteria for graft-threatening stenosis may not be valid for abnormalities at the proximal anastomosis of infrainguinal grafts. Regression of these abnormalities is common. Better CDU criteria are needed for predicting not only severity of proximal anastomotic stenosis but also likelihood of graft thrombosis.
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Affiliation(s)
- S V Ryan
- Section of Vascular Surgery, Pennsylvania Hospital, Philadelphia 19106, USA
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19
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Lombardi JV, Dougherty MJ, Calligaro KD, Campbell FJ, Schindler N, Raviola C. Predictors of outcome when reoperating for early infrainguinal bypass occlusion. Ann Vasc Surg 2000; 14:350-5. [PMID: 10943786 DOI: 10.1007/s100169910080] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The purpose of this study is to identify factors that predict outcome after intervention for early (<30 days) infrainguinal graft thrombosis. We reviewed the medical records, arteriograms, and follow-up studies of patients who underwent infrainguinal bypass for limb salvage between 8/91 and 9/98 and whose graft failed <30 days from the index procedure. Five factors were analyzed: (1) conduit: single segment saphenous vein versus alternative vein or composite conduit (20 vs. 13 patients); (2) repair modality: construction of a new graft at the time of the initial take-back procedure versus local revision and/or thrombectomy alone (12 vs. 21 patients); (3) run-off: good run-off versus poor run-off (20 vs. 13 patients); (4) operative findings: the presence of a correctable problem versus noncorrectable problem (20 vs. 13 patients); and (5) surgical history: previous versus no previous ipsilateral bypass (16 vs. 17 patients). These variables are statistically significant risk factors that can be used in combination to predict outcome. Unless a focal lesion clearly responsible for graft occlusion is found, complete graft replacement should be considered even if the new bypass must be prosthetic. The costs and morbidity of repeated procedures argue for primary amputation when adverse risk factors exist.
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Affiliation(s)
- J V Lombardi
- Section on Vascular Surgery, Pennsylvania Hospital, Philadelphia 19106, USA
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20
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Hiatt JG, Raviola C, Baker JD, Busuttil RW, Machleder HI, Moore WS. The limitations of predictability of success of femoral-popliteal bypass grafts. J Vasc Surg 1984; 1:617-22. [PMID: 6502831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
This study was carried out to determine whether we could develop a model to identify predictive factors for success of femoral-popliteal (FP) bypass grafts. In a retrospective review of 199 operations, 24 factors influencing outcome were selected by stepwise logistic regression analysis, a sophisticated, multifactorial computer program. The top five indicators (excluding intraoperative technical problems) were runoff status, previous ipsilateral FP bypass, preoperative prediction of potential amputation level, concurrent proximal vascular reconstruction, and site of the distal anastomosis. We chose to validate the predictive model developed before applying it clinically. Data from 67 subsequent cases were presented to the computer without the known outcome, and the probability of 30-day patency was calculated. The model predicted 11 failures; there were actually eight thromboses in the 67 grafts. However, only three of the failures were predicted correctly, and eight cases of computer-anticipated thromboses were patent at 30 days. The high false positive rate makes the clinical application of the predictive model inappropriate. The success of FP bypass grafts appears to be related to factors that cannot be assessed preoperatively, such as technical problems during surgery. Even those which seem to have a poor runoff and other high-risk factors may succeed; thus an aggressive approach is justified in lower extremity reconstructions.
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Dixon S, Pais SO, Raviola C, Gomes A, Machleder HI, Baker JD, Busuttil RW, Barker WF, Moore WS. Natural history of nonstenotic, asymptomatic ulcerative lesions of the carotid artery. A further analysis. Arch Surg 1982; 117:1493-8. [PMID: 7138306 DOI: 10.1001/archsurg.1982.01380350079011] [Citation(s) in RCA: 91] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The natural history of 153 asymptomatic, nonstenotic ulcerative lesions of the carotid bifurcation in 141 patients was reviewed. A technique for quantitatively defining small (A), large (B), and compound (C) ulcers was developed. During the course of study, extending up to ten years, 3% of patients with A ulcers, 21% with B ulcers, and 19% with C ulcers had hemispheric strokes without antecedent transient ischemic attacks (TIAs), on the side appropriate to the lesion. The interval annual stroke rate was 4.5% for B ulcers and 7.5% for C ulcers. Because these interval stroke rates are comparable to the 6% annual stroke rate occurring in patients with TIAs, a well-accepted indication for operation, we recommend prophylactic operation for these lesions in good surgical candidates, to be performed by surgeons who have demonstrably low operative stroke rates.
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Raviola C, Baker JD, Cousins A, Dix D. Evaluation of extracranial cerebrovascular disease in the hypertensive patient with ocular pneumoplethysmography at 500 mm Hg. Am J Surg 1982; 144:306-8. [PMID: 7114366 DOI: 10.1016/0002-9610(82)90006-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
OPG-300 is a reliable noninvasive method of detecting hemodynamically significant stenoses of the internal carotid circulation. An important limitation of the method is that patients with systemic blood pressure greater than 160 mm Hg cannot be studied; in our laboratory this represented 55 percent of the patients referred for testing. The addition of the 500 mm Hg vacuum modification now allows us to reliably test 95 percent of patients referred to our laboratory for evaluation of the extracranial cerebrovascular circulation.
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