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Zhou R, Grant J, Goldberg EM, Ryland D, Aliani M. Investigation of low molecular weight peptides (<1 kDa) in chicken meat and their contribution to meat flavor formation. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2019; 99:1728-1739. [PMID: 30226639 DOI: 10.1002/jsfa.9362] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 09/04/2018] [Accepted: 09/09/2018] [Indexed: 05/26/2023]
Abstract
BACKGROUND Low molecular weight peptides (LMWPs) (<1 kDa) generated in meat during chilled conditioning can act as flavor precursors in the Maillard reaction with a potential contribution to key volatile organic compound (VOC) formation upon heating. Liquid chromatography/quadrupole time-of-flight mass spectrometry (LC/QTOF-MS) successfully detected 44 LMWPs in chicken breast and thigh muscles stored at 4 °C for up to 6 days. Carnosine (350 mg per 100 g), glutathione (GSH, 20 mg per 100 g) (concentrations based on reported values in the literature) and cysteine glycine (Cys Gly, 5 mg per 100 g) (concentration based on results from LC/QTOF-MS) were used in model systems containing ribose (25 mg per 100 g). The three model systems were heated at 180 °C for 2 h at pH 6.3. VOCs were measured by simultaneous distillation solvent extraction/gas chromatography/mass spectrometry. RESULTS Of 33 VOCs detected, 26 were significantly different (P ≤ 0.05) between the three peptides. The majority of nitrogen-containing volatiles, pyrazines and pyridines, dominated the carnosine mixture, while sulfur-containing VOCs dominated the GSH and Cys Gly peptide mixtures. CONCLUSION Known key aroma compounds such as thiazole (meaty), 2-methyl-3-furanthiol (beef and meat), 2-furfurylthiol (roasted), dihydro-2-methyl-3(2H)-thiophenone (meaty), 2-acetylthiazole (meaty and roasted) and pyrazine (meaty) were detected under conditions specific to aged and thermally treated chicken, suggesting a potential contribution to the overall sensory quality of cooked meat. © 2018 Society of Chemical Industry.
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Affiliation(s)
- Ruiyin Zhou
- Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, Canada
| | - Jennifer Grant
- Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, Canada
| | - Erin M Goldberg
- Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, Canada
| | - Donna Ryland
- Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, Canada
| | - Michel Aliani
- Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, Canada
- The Canadian Centre for Agri-Food Research in Health and Medicine (CCARM), St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, Canada
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Stoyanov ES. The salts of chloronium ions R-Cl(+)-R (R = CH3 or CH2Cl): formation, thermal stability, and interaction with chloromethanes. Phys Chem Chem Phys 2016; 18:12896-904. [PMID: 27104946 DOI: 10.1039/c6cp00946h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The interaction of CH3Cl/CD3Cl or CH2Cl2/CD2Cl2 with the carborane acid H(CHB11Cl11) (abbreviated as H{Cl11}) generates the salts of CH3-{Cl11} and CH2Cl-{Cl11} and their deuterio analogs, respectively, which are analogs of the salts of asymmetric chloronium cations. Next, salts of chloronium cations CH3-Cl(+)-CH3, ClCH2-Cl(+)-CH2Cl, and ClCH2-Cl(+)-CH3 and their deuterio analogs were obtained from the above compounds. The asymmetric ClCH2-Cl(+)-CH3 cation was found to be unstable, and at ambient temperature, slowly disproportionated into symmetric cations (CH3)2Cl(+) and (CH2Cl)2Cl(+). At a high temperature (150 °C), disproportionation was completed within 5 minutes, and the resulting cations further decomposed into CH3-{Cl11} and CH2Cl-{Cl11}. The molecular fragment ClCH2-(X) of the compounds (X = {Cl11}, -Cl(+)-CH2Cl, or -Cl(+)-CH3) is involved in exchange reactions with CH2Cl2 and CHCl3, converting into CH3-(X) with the formation of chloroform and CCl4, respectively.
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Affiliation(s)
- Evgenii S Stoyanov
- Vorozhtsov Institute of Organic Chemistry, Siberian Branch of Russian Academy of Sciences (SB RAS), Novosibirsk 630090, Russia.
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Yue L, Guo C, Chai Y, Yin X, Pan Y. Gas-phase reaction: alkyl cation transfer in the dissociation of protonated pyridyl carbamates in mass spectrometry. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.10.067] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Methyl-to-double bond transfer in the gas phase: A theoretical study. COMPUT THEOR CHEM 2013. [DOI: 10.1016/j.comptc.2013.07.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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5
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Theoretical studies on intramolecular methyl transfer in the 2-methoxy-pyridine derivative radical cations. COMPUT THEOR CHEM 2012. [DOI: 10.1016/j.comptc.2012.03.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Yoo EJH, Feketeová L, Khairallah GN, O'Hair RAJ. Intercluster reactions show that (CH3)2S(+)CH2CO2H is a better methyl cation donor than (CH3)3N(+)CH2CO2H. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2011; 17:159-166. [PMID: 21719924 DOI: 10.1255/ejms.1115] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The intrinsic methylating abilities of the known biological methylating zwitterionic agents, dimethylsulfonioacetate (DMSA), (CH(3))(2)S⁺CH(2)CO(2)(-) (1) and glycine betaine (GB), (CH(3))(3)N⁺CH(2)CO(2)(-) (2), have been examined via a range of gas phase experiments involving collision-induced dissociation (CID) of their proton-bound homo- and heterodimers, including those containing the amino acid arginine. The relative yields of the products of methyl cation transfer are consistent in all cases and show that protonated DMSA is a more potent methylating agent than protonated GB. Since methylation can occur at more than one site in arginine, the [M+CH(3)](+) ion of arginine, formed from the heterocluster [DMSA+Arg+H](+), was subject to an additional stage of CID. The resultant CID spectrum is virtually identical to that of an authentic sample of protonated arginine-O-methyl ester but is significantly different to that of an authentic sample of protonated N(G)-methyl arginine. This suggests that methylation has occurred within a salt bridge complex of [DMSA+Arg+H](+), in which the arginine exists in the zwitterionic form. Finally, density functional theory calculations on the model salts, (CH(3)CO(2)(-))[(CH(3))(3)S(+)] and (CH(3)CO(2)(-))[(CH(3))(4)N(+)], show that methylation of CH(3)CO(2)(-) by (CH(3))(3)S(+) is both kinetically and thermodynamically preferred over methylation by (CH(3))(4)N(+).
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Affiliation(s)
- Evgenii S. Stoyanov
- Department of Chemistry, University of California, Riverside, California 92521-0403
| | - Irina V. Stoyanova
- Department of Chemistry, University of California, Riverside, California 92521-0403
| | - Fook S. Tham
- Department of Chemistry, University of California, Riverside, California 92521-0403
| | - Christopher A. Reed
- Department of Chemistry, University of California, Riverside, California 92521-0403
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Chaudret R, Trinquier G, Poteau R, Maron L. Theoretical proposal for an organometallic route to cis-peptides. NEW J CHEM 2009. [DOI: 10.1039/b904139g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Jubert A, Okulik N, Michelini MDC, Mota CJA. Topological Insights into the Nature of the Halogen−Carbon Bonds in Dimethylhalonium Ylides and Their Cations. J Phys Chem A 2008; 112:11468-80. [DOI: 10.1021/jp805699x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alicia Jubert
- CEQUINOR, Centro de Química Inorgánica (CONICET, UNLP), Departamento de Química, Facultad de Ciencias Exactas, UNLP, C. C. 962, 1900 La Plata, and Facultad de Ingeniería, UNLP, 1 y 47, 1900 La Plata, Argentina; Facultad de Agroindustrias, UNNE, Cte. Fernández 755, (3700) Pcia. R. Sáenz Peña, Chaco, Argentina; Dipartimento di Chimica and Centro di Calcolo ad Alte Prestazioni per Elaborazioni Parallele e Distribuite-Centro d’Eccellenza MURST, Università della Calabria, I-87030 Arcavacata di Rende, Italy
| | - Nora Okulik
- CEQUINOR, Centro de Química Inorgánica (CONICET, UNLP), Departamento de Química, Facultad de Ciencias Exactas, UNLP, C. C. 962, 1900 La Plata, and Facultad de Ingeniería, UNLP, 1 y 47, 1900 La Plata, Argentina; Facultad de Agroindustrias, UNNE, Cte. Fernández 755, (3700) Pcia. R. Sáenz Peña, Chaco, Argentina; Dipartimento di Chimica and Centro di Calcolo ad Alte Prestazioni per Elaborazioni Parallele e Distribuite-Centro d’Eccellenza MURST, Università della Calabria, I-87030 Arcavacata di Rende, Italy
| | - Maria del Carmen Michelini
- CEQUINOR, Centro de Química Inorgánica (CONICET, UNLP), Departamento de Química, Facultad de Ciencias Exactas, UNLP, C. C. 962, 1900 La Plata, and Facultad de Ingeniería, UNLP, 1 y 47, 1900 La Plata, Argentina; Facultad de Agroindustrias, UNNE, Cte. Fernández 755, (3700) Pcia. R. Sáenz Peña, Chaco, Argentina; Dipartimento di Chimica and Centro di Calcolo ad Alte Prestazioni per Elaborazioni Parallele e Distribuite-Centro d’Eccellenza MURST, Università della Calabria, I-87030 Arcavacata di Rende, Italy
| | - Claudio J. A. Mota
- CEQUINOR, Centro de Química Inorgánica (CONICET, UNLP), Departamento de Química, Facultad de Ciencias Exactas, UNLP, C. C. 962, 1900 La Plata, and Facultad de Ingeniería, UNLP, 1 y 47, 1900 La Plata, Argentina; Facultad de Agroindustrias, UNNE, Cte. Fernández 755, (3700) Pcia. R. Sáenz Peña, Chaco, Argentina; Dipartimento di Chimica and Centro di Calcolo ad Alte Prestazioni per Elaborazioni Parallele e Distribuite-Centro d’Eccellenza MURST, Università della Calabria, I-87030 Arcavacata di Rende, Italy
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Lioe H, O'Hair RAJ. A novel salt bridge mechanism highlights the need for nonmobile proton conditions to promote disulfide bond cleavage in protonated peptides under low-energy collisional activation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2007; 18:1109-23. [PMID: 17462910 DOI: 10.1016/j.jasms.2007.03.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2007] [Revised: 03/08/2007] [Accepted: 03/09/2007] [Indexed: 05/15/2023]
Abstract
The gas-phase fragmentation mechanisms of small models for peptides containing intermolecular disulfide links have been studied using a combination of tandem mass spectrometry experiments, isotopic labeling, structural labeling, accurate mass measurements of product ions, and theoretical calculations (at the MP2/6-311 + G(2d,p)//B3LYP/3-21G(d) level of theory). Cystine and its C-terminal derivatives were observed to fragment via a range of pathways, including loss of neutral molecules, amide bond cleavage, and S-S and C-S bond cleavages. Various mechanisms were considered to rationalize S-S and C-S bond cleavage processes, including charge directed neighboring group processes and nonmobile proton salt bridge mechanism. Three low-energy fragmentation pathways were identified from theoretical calculations on cystine N-methyl amide: (1) S-S bond cleavage dominated by a neighboring group process involving the C-terminal amide N to form either a protonated cysteine derivative or protonated sulfenyl amide product ion (44.3 kcal mol(-1)); (2) C-S bond cleavage via a salt bridge mechanism, involving abstraction of the alpha-hydrogen by the N-terminal amino group to form a protonated thiocysteine derivative (35.0 kcal mol(-1)); and (3) C-S bond cleavage via a Grob-like fragmentation process in which the nucleophilic N-terminal amino group forms a protonated dithiazolidine (57.9 kcal mol(-1)). Interestingly, C-S bond cleavage by neighboring group processes have high activation barriers (63.1 kcal mol(-1)) and are thus not expected to be accessible during low-energy CID experiments. In comparison to the energetics of simple amide bond cleavage, these S-S and C-S bond cleavage reactions are higher in energy, which helps rationalize why bond cleavage processes involving the disulfide bond are rarely observed for low-energy CID of peptides with mobile proton(s) containing intermolecular disulfide bonds. On the other hand, the absence of a mobile proton appears to "switch on" disulfide bond cleavage reactions, which can be rationalized by the salt bridge mechanism. This potentially has important ramifications in explaining the prevalence of disulfide bond cleavage in singly protonated peptides under MALDI conditions.
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Affiliation(s)
- Hadi Lioe
- School of Chemistry, University of Melbourne, Melbourne, Australia
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11
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Zhang X, Wang H, Liao Y, Ji H, Guo Y. Study of methylation of nitrogen-containing compounds in the gas phase. JOURNAL OF MASS SPECTROMETRY : JMS 2007; 42:218-24. [PMID: 17173336 DOI: 10.1002/jms.1154] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The methyl migration between the protonated N,N-dimethylisopropylamine and other neutral aliphatic amines in the gas phase has been investigated by a hybrid external chemical ionization source ion trap mass spectrometer. Similar reactions have been found in the aqueous solution by Callahan and Wolfenden (J. Am. Chem. Soc. 2003; 125: 310). At the same time, density functional theory (DFT) calculations show that in contrast with the neutral N,N-dimethylisopropylamine, protonated N,N-dimethylisopropylamine is a better methyl donor. These results indicate that protonation promotes the methyl migration between aliphatic amines both in the gas phase and in the aqueous solution. In addition, methyl transfer also exists between the protonated N,N-dimethylisopropylamine and some other nitrogen-containing compounds.
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Affiliation(s)
- Xiang Zhang
- Shanghai Mass Spectrometry Center, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
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12
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Noronha LA, Judson TJL, Dias JF, Santos LS, Eberlin MN, Mota CJA. Intrinsic Acidity of Dimethylhalonium Ions: Evidence for Hyperconjugation in Dimethylhalonium Ylides in the Gas Phase. J Org Chem 2006; 71:2625-9. [PMID: 16555813 DOI: 10.1021/jo052439l] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The intrinsic acidity of dimethylhalonium ions has been determined, both by theoretical methods and by gas-phase reactions of the isolated ions with pyridine bases. The calculated geometry of the dimethylhalonium ions shows a bent structure with the C-X-C angle decreasing in the order Cl > Br > I. Thermochemical calculations for the reaction of the dimethylhalonium ions with pyridine, 2,6-dimethylpyridine, and 2,6-di-tert-butylpyridine indicate that proton transfer, with the formation of the dimethylhalonium ylide is endothermic, whereas methyl transfer, with formation of methylhalide, is exothermic. The endothermicities for proton transfer are, nevertheless, dependent on the steric hindrance of the base. The bulkier the bases, the less endothermic the proton-transfer reaction is. Experimental gas-phase reactions support the calculations, showing that methyl transfer is the major reaction of dimethylchloronium and dimethyliodonium with pyridine, whereas proton transfer, as well as single electron transfer, is observed for the bulkier bases. The calculations also indicate that acidity increases in the order chloronium > bromonium > iodonium. NBO calculations predict that hyperconjugation with the sigma carbon-halogen orbital plays a role in stabilizing the halonium ylide species in the gas phase.
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Affiliation(s)
- Leandro A Noronha
- Universidade Federal do Rio de Janeiro, Instituto de Química, Departamento Química Orgânica, Cidade Universitaria CT Bloco A, 21949-900 Rio de Janeiro, Brazil
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13
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Physical Organic Chemistry of the Gas Phase. Reactivity Trends for Organic Cations. Top Curr Chem (Cham) 2003. [DOI: 10.1007/3-540-36113-8_1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
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Moraes LAB, Eberlin MN. Structurally diagnostic ion-molecule reactions: acylium ions with alpha-, beta- and gamma-hydroxy ketones. JOURNAL OF MASS SPECTROMETRY : JMS 2002; 37:162-168. [PMID: 11857760 DOI: 10.1002/jms.270] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Gas-phase reactions of four acylium ions and a thioacylium ion with three isomeric alpha-, beta- and gamma-hydroxy ketones are performed by pentaquadrupole mass spectrometric experiments. Novel structurally diagnostic reactions are observed, and found to correlate directly with interfunctional group separation. All five ions tested (CH(3)CO(+), CH(2)(double bond)CHCO(+), PhCO(+), (CH(3))(2)NCO(+) and (CH(3))(2)NCS(+)) react with the gamma-hydroxy ketone (5-hydroxy-2-pentanone) to form nearly exclusively a cyclic oxonium ion of m/z 85 that formally arises from hydroxy anion abstraction. With the beta-hydroxy ketone (4-hydroxy-2-pentanone), CH(2)(double bond)CHCO(+), PhCO(+) and (CH(3))(2)NCO(+) form adducts that undergo fast cyclization via intramolecular water displacement, yielding resonance-stabilized cyclic dioxinylium ions. With the alpha-hydroxy ketone (3-hydroxy-3-methyl-2-butanone), PhCO(+), (CH(3))(2)NCO(+) and (CH(3))(2)NCS(+) form stable adducts. Evidence that these adducts display cyclic structures is provided by the triple-stage mass spectra of the (CH(3))(2)NCS(+) adduct; it dissociates to (CH(3))(2)NCO(+) via a characteristic reaction-dissociation pathway that promotes sulfur-by-oxygen replacement. If cyclizations are assumed to occur with intramolecular anchimeric assistance, relationships between structure and reactivity are easily recognized.
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Affiliation(s)
- L A B Moraes
- Institute of Chemistry, State University of Campinas-UNICAMP, CP 6154, 13083-970 Campinas, SP, Brazil
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Abstract
In the past 25 years, a tremendous amount of work has been published on the ion/molecule reactions of organic species. This review provides an overview of the areas where gas phase ion chemistry has made a contribution to our understanding of fundamental organic reaction processes. It is clear that the gas phase work can provide insights into subtle features of reaction mechanisms that could not be addressed by conventional condensed phase methods. The study of ion/molecule reactions has already had a major impact on the way that organic chemists think about reaction mechanisms and interpret substituent effects. Moreover, it has heightened our awareness of the importance of solvation effects and how they can alter not only absolute rates but also relative rates, leading in some cases to complete reversals in reactivity patterns. A large body of work could not be included in this review due to space limitations. For example, the study of thermochemistry in the gas phase (i.e., acidities, basicities, bond strengths, binding energies, etc.) has provided a wealth of data that has been exceptionally useful in interpreting organic reaction mechanisms. This has spilled over into the study of organometallic systems, and several groups are making major headway in using mass spectrometry to probe the stability and reactivity of transition metal species. Finally, work involving chemical ionization has provided abundant information on gas phase reaction mechanisms. The future appears to be very promising for the study of gas phase organic reaction mechanisms. In particular, the emergence of new ionization techniques and more powerful mass analyzers will allow chemists to explore a wider range of species. Although still at an early stage, the gas phase study of biochemical transformations offers great promise and has been facilitated by electrospray and matrix assisted laser desorption ionization methods. In addition, these techniques provide a means for introducing important, metal-centered catalytic species into the gas phase and exploring the details of their reactivity. Finally, mass spectrometry continues to play a major role in the study of atmospheric ion chemistry and is providing important kinetic as well as mechanistic data.
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Affiliation(s)
- S Gronert
- Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, California 94132, USA
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Moraes LA, Eberlin MN. Ketalization of gaseous acylium ions. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2001; 12:150-162. [PMID: 11212000 DOI: 10.1016/s1044-0305(00)00211-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A novel reaction of gaseous acylium ions: ketalization with diols and analogs, has been systematically studied via pentaquadrupole MS2 and MS3 experiments and ab initio calculations. A variety of alpha,beta-diols and their amino, thiol, ether, and thioether analogs have been tested for reactivity, mechanism evaluation, site selectivity, and for the effects of alpha- and beta-interfunctional separation. As for condensed-phase ketalization of neutral carbonyl compounds followed by hydrolysis, gaseous acylium ions are chemically deactivated in the form of cyclic ionic ketals by ketalization, and are efficiently released via on-line collision-induced dissociation. Ketalization of acylium ions is shown to identify and structurally characterize alpha,beta-diols and their analogs, and to distinguish regioisomers. Diastereomers can also be distinguished, as illustrated for cis and trans 1,2-diaminocyclohexane. The MS2 and MS3 data together with 18O-labeling and ab initio calculations establish for acylium ion ketalization a mechanism of anchimeric assistance with participation of the neighboring acyl group.
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Affiliation(s)
- L A Moraes
- State University of Campinas-UNICAMP, Institute of Chemistry, SP Brazil
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Dantanarayana AP, Dupre B, May JA, Lynch VM. A convenient synthesis of the novel 5H-thieno[2,3-e]-4,1,2-oxathiazepine ring systemviaan alkoxycarbenium ion intermediate. J Heterocycl Chem 1999. [DOI: 10.1002/jhet.5570360111] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Freitas MA, O'Hair RA. Characterization of an ambident electrophile: the gas phase reactivity of the methoxymethyl cation. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0168-1176(98)00126-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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