Many methods exist for the organic synthesis of pyrazine and its derivatives. Some of these are among the oldest synthesis reactions still in use.
In the Staedel–Rugheimer pyrazine synthesis (1876), 2-chloroacetophenone is reacted with ammonia to the amino ketone, then condensed and then oxidized to a pyrazine.[5] A variation is the Gutknecht pyrazine synthesis (1879) also based on this selfcondensation, but differing in the way the alpha-ketoamine is synthesised.[6][7]
The Gastaldi synthesis (1921) is another variation:[8][9]
^Brown, H.C., et al., in Baude, E.A. and Nachod, F.C., Determination of Organic Structures by Physical Methods, Academic Press, New York, 1955.
^"Pyrazine | C4H4N2 | ChemSpider". www.chemspider.com. Retrieved 4 January 2022.
^Zhang, Zhaohui (2003). "Tetramethylpyrazine scavenges superoxide anion and decreases nitric oxide production in human polymorphonuclear leukocytes". Life Sciences. 72 (22): 2465–2472. doi:10.1016/S0024-3205(03)00139-5. PMID 12650854.
^Ueber die Einwirkung von Ammoniak auf Chloracetylbenzol (pp. 563–564) W. Staedel, L. Rügheimer doi:10.1002/cber.187600901174 Berichte der deutschen chemischen Gesellschaft Volume 9, Issue 1, pp. 563–564, 1876
^Amines: Synthesis, Properties and Applications Stephen A. Lawrence 2004 Cambridge University Press ISBN0-521-78284-8
External linksEdit
Safety evaluation of food additives – pyrazine derivatives
October 16, 2023
pyrazine, heterocyclic, aromatic, organic, compound, with, chemical, formula, c4h4n2, symmetrical, molecule, with, point, group, less, basic, than, pyridine, pyridazine, pyrimidine, deliquescent, crystal, like, solid, with, pungent, sweet, corn, like, nutty, o. Pyrazine is a heterocyclic aromatic organic compound with the chemical formula C4H4N2 It is a symmetrical molecule with point group D2h Pyrazine is less basic than pyridine pyridazine and pyrimidine It is a deliquescent crystal or wax like solid with a pungent sweet corn like nutty odour 3 Pyrazine NamesPreferred IUPAC name Pyrazine 1 Other names 1 4 Diazabenzene p Diazine 1 4 Diazine Paradiazine Piazine UN 1325IdentifiersCAS Number 290 37 9 Y3D model JSmol Interactive imageChEBI CHEBI 30953 YChEMBL ChEMBL15797 YChemSpider 8904 YECHA InfoCard 100 005 480EC Number 206 027 6PubChem CID 9261UNII 2JKE371789 YCompTox Dashboard EPA DTXSID8049410InChI InChI 1S C4H4N2 c1 2 6 4 3 5 1 h1 4H YKey KYQCOXFCLRTKLS UHFFFAOYSA N YInChI 1 C4H4N2 c1 2 6 4 3 5 1 h1 4HSMILES c1cnccn1PropertiesChemical formula C4H4N2Molar mass 80 09 g molAppearance White crystalsDensity 1 031 g cm3Melting point 52 C 126 F 325 K Boiling point 115 C 239 F 388 K Solubility in water SolubleAcidity pKa 0 37 2 protonated pyrazine Magnetic susceptibility x 37 6 10 6 cm3 molHazardsGHS labelling PictogramsSignal word DangerHazard statements H228 H315 H319 H335Precautionary statements P210 P261 P305 P351 P338NFPA 704 fire diamond 220Flash point 55 C 131 F 328 K c c Except where otherwise noted data are given for materials in their standard state at 25 C 77 F 100 kPa Y verify what is Y N Infobox references Pyrazine and a variety of alkylpyrazines are flavor and aroma compounds found in baked and roasted goods Tetramethylpyrazine also known as ligustrazine is reported to scavenge superoxide anion and decrease nitric oxide production in human Granulocytes 4 Contents 1 Synthesis 2 See also 3 References 4 External linksSynthesis EditMany methods exist for the organic synthesis of pyrazine and its derivatives Some of these are among the oldest synthesis reactions still in use In the Staedel Rugheimer pyrazine synthesis 1876 2 chloroacetophenone is reacted with ammonia to the amino ketone then condensed and then oxidized to a pyrazine 5 A variation is the Gutknecht pyrazine synthesis 1879 also based on this selfcondensation but differing in the way the alpha ketoamine is synthesised 6 7 nbsp The Gastaldi synthesis 1921 is another variation 8 9 nbsp See also EditAlkylpyrazines Benzene an analog without the nitrogen atoms Methoxypyrazines Pyridazine an analog with the second nitrogen atom in position 2 Pyridine an analog with only one nitrogen atom Pyrimidine an analog with the second nitrogen atom in position 3 Simple aromatic ringsReferences Edit International Union of Pure and Applied Chemistry 2014 Nomenclature of Organic Chemistry IUPAC Recommendations and Preferred Names 2013 The Royal Society of Chemistry p 141 doi 10 1039 9781849733069 ISBN 978 0 85404 182 4 Brown H C et al in Baude E A and Nachod F C Determination of Organic Structures by Physical Methods Academic Press New York 1955 Pyrazine C4H4N2 ChemSpider www chemspider com Retrieved 4 January 2022 Zhang Zhaohui 2003 Tetramethylpyrazine scavenges superoxide anion and decreases nitric oxide production in human polymorphonuclear leukocytes Life Sciences 72 22 2465 2472 doi 10 1016 S0024 3205 03 00139 5 PMID 12650854 Ueber die Einwirkung von Ammoniak auf Chloracetylbenzol pp 563 564 W Staedel L Rugheimer doi 10 1002 cber 187600901174 Berichte der deutschen chemischen Gesellschaft Volume 9 Issue 1 pp 563 564 1876 Mittheilungen Ueber Nitrosoathylmethylketon H Gutknecht Berichte der deutschen chemischen Gesellschaft Volume 12 Issue 2 pp 2290 2292 1879 doi 10 1002 cber 187901202284 Heterocyclic chemistry T L Gilchrist ISBN 0 582 01421 2 G Gastaldi Gazz Chim Ital 51 1921 233 Amines Synthesis Properties and Applications Stephen A Lawrence 2004 Cambridge University Press ISBN 0 521 78284 8External links EditSafety evaluation of food additives pyrazine derivatives Retrieved from https en wikipedia org w index php title Pyrazine amp oldid 1118573019, wikipedia, wiki, book, books, library,
