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Li J, Khairallah GN, O'Hair RAJ. Decarboxylation versus Acetonitrile Loss in Silver Acetate and Silver Propiolate Complexes, [RCO2Ag2(CH3CN)n]+ (where R = CH3 and CH3C≡C; n = 1 and 2). Aust J Chem 2015. [DOI: 10.1071/ch15210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Gas-phase experiments using collision-induced dissociation in an ion trap mass spectrometer have been used in combination with density functional theory (DFT) calculations (at the B3LYP/SDD6–31+G(d) level of theory) to examine the competition between decarboxylation and loss of a coordinated acetonitrile in the unimolecular fragmentation reactions of the silver acetate and silver propiolate complexes, [RCO2Ag2(CH3CN)n]+ (where R = CH3 and CH3C≡C; n = 1 and 2), introduced into the gas-phase via electrospray ionisation. When R = CH3, loss of acetonitrile is the sole reaction channel observed for both complexes (n = 1 and 2), consistent with DFT calculations, which highlight that the barriers for decarboxylation 2.18 eV (n = 2) and 1.96 eV (n = 1) are greater than the binding energies of the coordinated acetonitriles (1.60 eV for n = 2; 1.64 eV for n = 1). In contrast, when R = CH3C≡C, decarboxylation is the main fragmentation pathway observed for both complexes (n = 1 and 2), with loss of acetonitrile only being a minor product channel. This is consistent with DFT calculations, which reveal that the barriers for decarboxylation are 1.17 eV (n = 2) and 1.16 eV (n = 1), which are both below the binding energies of the coordinated acetonitriles (1.55 eV for n = 2; 1.56 eV for n = 1). The barrier for decarboxylation of [CH3C≡CCO2Ag2]+ is 1.22 eV, which is less than the 2.06 eV reported for decarboxylation of [CH3CO2Ag2]+ (Al Sharif et al. Organometallics, 2013, 32, 5416). The observed ease of decarboxylation of silver propiolate complexes in the gas-phase is consistent with the recently reported use of silver salts in metal catalysed decarboxylative C–C and C–X bond forming reactions of propiolic acids.
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Al Sharif H, Vikse KL, Khairallah GN, O’Hair RAJ. Catalytic Decarboxylative Coupling of Allyl Acetate: Role of the Metal Centers in the Organometallic Cluster Cations [CH3Cu2]+, [CH3AgCu]+, and [CH3Ag2]+. Organometallics 2013. [DOI: 10.1021/om400712n] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Halah Al Sharif
- School of Chemistry, The University of Melbourne, Melbourne, Victoria 3010, Australia
- Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Melbourne, Victoria 3010, Australia
- ARC Centre of Excellence for Free Radical Chemistry
and Biotechnology, The University of Melbourne, Melbourne, Victoria 3010, Australia
- Ministry of Higher Education, Saudi Arabia
| | - Krista L. Vikse
- School of Chemistry, The University of Melbourne, Melbourne, Victoria 3010, Australia
- Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - George N. Khairallah
- School of Chemistry, The University of Melbourne, Melbourne, Victoria 3010, Australia
- Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Richard A. J. O’Hair
- School of Chemistry, The University of Melbourne, Melbourne, Victoria 3010, Australia
- Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Melbourne, Victoria 3010, Australia
- ARC Centre of Excellence for Free Radical Chemistry
and Biotechnology, The University of Melbourne, Melbourne, Victoria 3010, Australia
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Rijs NJ, Yoshikai N, Nakamura E, O’Hair RAJ. Gas-Phase Reactivity of Group 11 Dimethylmetallates with Allyl Iodide. J Am Chem Soc 2012; 134:2569-80. [DOI: 10.1021/ja2069032] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nicole J. Rijs
- ARC Centre of Excellence for Free Radical Chemistry and Biotechnology
| | - Naohiko Yoshikai
- Division of Chemistry and Biological
Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
| | - Eiichi Nakamura
- Department of Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033,
Japan
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Khairallah GN, Waters T, O'Hair RAJ. C–C bond coupling between the organometallic cations CH3Ag2+, CH3Cu2+ and CH3AgCu+ and allyliodide. Dalton Trans 2009:2832-6. [DOI: 10.1039/b822371h] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Khairallah GN, O'Hair RAJ. Gas phase synthesis, structure and unimolecular reactivity of silver iodide cluster cations, AgnIm+ (n = 2–5, 0 < m < n). Dalton Trans 2008:2956-65. [DOI: 10.1039/b719274f] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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