Quinaldine

Quinaldine

Names
Preferred IUPAC name 2-Methylquinoline
Other names Quinaldine, α-methylquinoline, chinaldine, khinaldin
Identifiers
CAS Number	91-63-4  Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:132813
ChEMBL	ChEMBL194931  Y
ChemSpider	13870160  Y
ECHA InfoCard	100.001.896
EC Number	202-085-1
PubChem CID	7060
UNII	DVG30M0M87  Y
CompTox Dashboard (EPA)	DTXSID3040271
InChI InChI=1S/C10H9N/c1-8-6-7-9-4-2-3-5-10(9)11-8/h2-7H,1H3 Y Key: SMUQFGGVLNAIOZ-UHFFFAOYSA-N Y InChI=1/C10H9N/c1-8-6-7-9-4-2-3-5-10(9)11-8/h2-7H,1H3
SMILES Cc1nc2ccccc2cc1
Properties
Chemical formula	C10H9N
Molar mass	143.19 g/mol
Appearance	colorless oil
Density	1.058 g/cm3
Melting point	−2 °C (28 °F; 271 K)
Boiling point	248 °C (478 °F; 521 K)
Solubility in water	Insoluble
Hazards
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H302, H312, H319
Precautionary statements	P264, P270, P280, P301+P312, P302+P352, P305+P351+P338, P312, P322, P330, P337+P313, P363, P501
NFPA 704 (fire diamond)	2 2 0
Flash point	79 °C (174 °F; 352 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N  verify  (what is  YN ?) Infobox references

Quinaldine or 2-methylquinoline is an organic compound with the formula CH₃C₉H₆N. It is one of the methyl derivatives of the heterocyclic compound quinoline. It is bioactive and is used in the preparation of various dyes. It is a colorless oil but commercial samples can appear colored. ^[1]

Production and reactions

Quinaldine is recovered from coal tar. It can be prepared from aniline and paraldehyde via Skraup synthesis or from aniline and crotonaldehyde via Doebner-von Miller variation of the Skraup reaction. ^[1]

Hydrogenation of quinaldine gives 2-methyltetrahydroquinoline. This reduction can be conducted enantioselectively. ^[2] Oxidation with selenium dioxide give the aldehyde 2-formylquinoline. ^[3]

Properties

Quinaldine has critical point at 787 K and 4.9 MPa and its refractive index is 1.8116.^{[ citation needed ]}

Uses

Quinoline Yellow is a popular dye derived from quinaldine.

Quinaldine Red, a pH indicating dye.

Quinaldine is used in manufacturing anti-malaria drugs, dyes and food colorants (e.g., Quinoline Yellows, pinacyanol). It is the precursor to the pH indicator Quinaldine Red.

Quinaldine sulfate is an anaesthetic used in fish transportation. ^[4] In some Caribbean islands it is used to facilitate the collection of tropical fish from reefs.

See also

• Lepidine, the isomer with the methyl group in position 4.

References

1. Gerd Collin; Hartmut Höke. "Quinoline and Isoquinoline". Ullmann's Encyclopedia of Industrial Chemistry . Weinheim: Wiley-VCH. doi:10.1002/14356007.a22_465. ISBN   978-3-527-30673-2.
2. Chen, Fei; Ding, Zi-Yuan; He, Yan-Mei; Fan, Qing-Hua (2015). "Synthesis of Optically Active 1,2,3,4-Tetrahydroquinolines via Asymmetric Hydrogenation Using Iridium-Diamine Catalyst". Org. Synth. 92: 213–226. doi: 10.15227/orgsyn.092.0213 .
3. H. A. Riley, A. R. Gray (1935). "Phenylglyoxal". Organic Syntheses. 15: 67. doi:10.15227/orgsyn.015.0067.
4. Blasiola G. C. Jr. (1977). "Quinaldine sulphate, a new anaesthetic formulation for tropical marine fishes". Journal of Fish Biology. 10 (2): 113–119(7). doi:10.1111/j.1095-8649.1977.tb04048.x.

External links

• MSDS at Science Lab Archived 2015-09-09 at the Wayback Machine
• Method of purifying quinaldine
• Chisholm, Hugh, ed. (1911). "Quinoline"  . Encyclopædia Britannica . Vol. 22 (11th ed.). Cambridge University Press. pp. 758–760.