Oxazines

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The 8 isomers of oxazine Oxazines.svg
The 8 isomers of oxazine

Oxazines are heterocyclic organic compounds containing one oxygen and one nitrogen atom in a cyclohexa-1,4-diene ring (a doubly unsaturated six-membered ring). Isomers exist depending on the relative position of the heteroatoms and relative position of the double bonds.

Contents

By extension, the derivatives are also referred to as oxazines; examples include ifosfamide and morpholine (tetrahydro-1,4-oxazine). A commercially available dihydro-1,3-oxazine is a reagent in the Meyers synthesis of aldehydes. Fluorescent dyes such as Nile red and Nile blue are based on the aromatic compound benzophenoxazine. Cinnabarine and cinnabaric acid are two naturally occurring dioxazines, being derived from biodegradation of tryptophan. [2]

Dioxazines

Dioxazines are pentacyclic compounds consisting of two oxazine subunits. A commercially important example is the pigment pigment violet 23. [3]

Synthetic route to dioxazine dyes. DioxazineFrChloranil.png
Synthetic route to dioxazine dyes.

Benzoxazines

Benzoxazine resin synthetic pathway, structure and cure mechanism Benzoxazine resins.jpg
Benzoxazine resin synthetic pathway, structure and cure mechanism

Benzoxazines are bicyclic compounds formed by the ring fusion of a benzene ring with an oxazine. Polybenzoxazines are a class of polymers formed by the reaction of phenols, formaldehyde, and primary amines which on heating to ~200 °C (~400 °F) polymerise to produce polybenzoxazine networks. [5] The resulting high molecular weight thermoset polymer matrix composites are used where enhanced mechanical performance, flame and fire resistance compared to epoxy and phenolic resins is required. [6]

Physical properties

Oxazine dyes exhibit solvatochromism. [7]

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Related Research Articles

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<span class="mw-page-title-main">Tetrahydrofuran</span> Cyclic chemical compound, (CH₂)₄O

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<span class="mw-page-title-main">Sulfonic acid</span> Organic compounds with the structure R−S(=O)2−OH

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<span class="mw-page-title-main">Triazine</span> Aromatic, heterocyclic compound

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<span class="mw-page-title-main">Organic peroxides</span> Organic compounds of the form R–O–O–R’

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<span class="mw-page-title-main">Fluorene</span> Chemical compound

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<span class="mw-page-title-main">Polyester</span> Category of polymers, in which the monomers are joined together by ester links

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The Gattermann reaction, (also known as the Gattermann formylation and the Gattermann salicylaldehyde synthesis) is a chemical reaction in which aromatic compounds are formylated by a mixture of hydrogen cyanide (HCN) and hydrogen chloride (HCl) in the presence of a Lewis acid catalyst such as AlCl3. It is named for the German chemist Ludwig Gattermann and is similar to the Friedel–Crafts reaction.

<span class="mw-page-title-main">Polybenzoxazine</span> Type of bicyclic heterocyclic monomer

Polybenzoxazines, also called benzoxazine resins, are cured polymerization products derived from benzoxazine monomers.

<span class="mw-page-title-main">Carbazole</span> Chemical compound

Carbazole is an aromatic heterocyclic organic compound. It has a tricyclic structure, consisting of two six-membered benzene rings fused on either side of a five-membered nitrogen-containing ring. The compound's structure is based on the indole structure, but in which a second benzene ring is fused onto the five-membered ring at the 2–3 position of indole.

<span class="mw-page-title-main">Diphenyl ether</span> Chemical compound

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<span class="mw-page-title-main">Alkylphenol</span> Family of organic compounds

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<span class="mw-page-title-main">Oxazoline</span> Chemical compound

Oxazoline is a five-membered heterocyclic organic compound with the formula C3H5NO. It is the parent of a family of compounds called oxazolines, which contain non-hydrogenic substituents on carbon and/or nitrogen. Oxazolines are the unsaturated analogues of oxazolidines, and they are isomeric with isoxazolines, where the N and O are directly bonded. Two isomers of oxazoline are known, depending on the location of the double bond.

<span class="mw-page-title-main">Bisphenol A diglycidyl ether</span> Chemical compound

Bisphenol A diglycidyl ether is an organic compound and is a liquid epoxy resin. The compound is a colorless viscous liquid. It is a key component of many epoxy resin formulations. Addition of further Bisphenol A and a catalyst and heat can produce Bisphenol A glycidyl ether epoxy resins of higher molecular weight that are solid.

<span class="mw-page-title-main">Benzoxazine</span>

Benzoxazines are a group of isomeric bicyclic heterocyclic chemical compounds that consist of a benzene ring fused to an oxazine ring. The different isomers depend on the relative positions of the oxygen and nitrogen atoms in the oxazine ring, on the location of ring fusion, and on the position of the double bond in the oxazine ring. They have the molecular formula C8H7NO.

<span class="mw-page-title-main">Pigment violet 23</span> Chemical compound

Pigment violet 23 is an organic compound that is a commercial pigment. It is member of the dioxazine family of heterocyclic compounds, but derived from carbazoles. It is prepared by condensation of chloranil and 3-amino-N-ethylcarbazole. It has a centrosymmetric angular structure. For many years, the structure was assigned, incorrectly, as having a "linear structure" which differ in terms of the carbazole ring fusion.

References

  1. Eicher T, Hauptmann S, Speicher A (March 2013). The Chemistry of Heterocycles: Structures, Reactions, Synthesis, and Applications (3rd ed.). Wiley Inc. p. 442. ISBN   978-3-527-66987-5. OCLC   836864122.
  2. Stone TW, Stoy N, Darlington LG (February 2013). "An expanding range of targets for kynurenine metabolites of tryptophan" (PDF). Trends in Pharmacological Sciences. 34 (2): 136–43. doi:10.1016/j.tips.2012.09.006. PMID   23123095.
  3. Chamberlain T (2002). "Dioxazine violet pigments". In Smith HM (ed.). High Performance Pigments. John Wiley & Sons. pp. 185–194. doi:10.1002/3527600493.ch12. ISBN   978-3-527-30204-8.
  4. Tappe H, Helmling W, Mischke P, Rebsamen K, Reiher U, Russ W, Schläfer L, Vermehren P (2000). "Reactive Dyes". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a22_651. ISBN   3527306730.
  5. Tsotra P, Setiabudi F, Weidmann U (2008). "Benzoxazine chemistry: a new material to meet fire retardant challenges of aerospace interiors applications" (PDF). Engineering. S2CID   18422389.
  6. Tietze R, Chaudhari M (2011). "Advanced benzoxazine chemistries provide improved performance in a broad range of applications". In Ishida H, Agag T (eds.). Handbook of Benzoxazine Resins. Elsevier B.V. pp. 595–604. doi:10.1016/B978-0-444-53790-4.00079-5. ISBN   978-0-444-53790-4.
  7. Fleming S, Mills A, Tuttle T (2011-04-15). "Predicting the UV-vis spectra of oxazine dyes". Beilstein Journal of Organic Chemistry. 7: 432–441. doi:10.3762/bjoc.7.56. PMC   3107493 . PMID   21647257.