10-Hydroxybenzo quinoline

The palladium-catalyzed reaction of benzol]quinoline in the presence of PhI(OAc)2 as an oxidant in MeCN gives an 11 1 mixture of 10-acetoxy- and 10-hydroxybenzo[ ]quinolines in 86% yield (Equation (98)).135 This chelation-directed oxidation can be extended to the benzylic C-H bond of 8-methylquinoline. The inactivated sp3 C-H bonds of oximes and pyridines undergo the same palladium-catalyzed oxidation with PhI(OAc)2 (Equation (99)).1... 

Figure 12.17 10-Hydroxybenzo[/)]quinoline side armed compounds.

Chou PT, Chen YC, Yu WS et al (2001) Excited-state intramolecular proton transfer in 10-hydroxybenzo[h]quinoline. J Phys Chem A 105 1731-1740... 

Takeuchi T, Tahara T (2005) Coherent nuclear wavepacket motions in ultrafast excited-state intramolecular proton transfer sub-30-fs resolved pump-probe absorption spectroscopy of 10-hydroxybenzo[h]quinoline in solution. J Phys Chem A 109 10199-10207... 

Roberts EL, Chou PT, Alexander TA et al (1995) Effects of organized media on the excited-state intramolecular proton transfer of 10-hydroxybenzo[h]quinoline. J Phys Chem 99 5431-5437... 

In some cases the reaction is accompanied by a five-membered heterocyclic ring closure. For example, l-nitro-4-methoxynaphthalene 265 reacts with p-tolylpro-penylsulfone to give benzo[/z]quinoline 266 (35%) together with A-hydroxybenzo-pyrrole derivative 267 (14%) (Scheme 77) (00EJO521). Annulation of the pyridine ring may proceed via anion 268, whereas the formation of benzoindole 267 occurs via neutral alkene 269. 

Dichlorophenol has been prepared by the chlorination of phenol with chlorine gas in the presence of nitrobenzene and fuming sulfuric acid, by the decomposition of the diazotate of 2,6 dichloro-4-aminophenol, eind by the decarboxylation of 3,5-dichloro-4-hydroxybenzoic acid in quinoline or dimethyl-aniline. ... 

In principle, most of the syntheses of quinolizones could be applied to the synthesis of benzoquinolizones by starting with the quinoline or isoquinoline equivalent of the pyridine component. Thus Kappe84 has obtained the hydroxybenzo[ ]quinolizin-4-ones 70, and the hydroxybenzo[c]quino-lizin-l-ones 71 from methylquinolines, quinolyl- or isoquinolylacetates, and malonic esters or carbon suboxide. Kato and co-workers37-38 have used the Vilsmeier derivatives of 2-quinolylacetate with diketene (Eq. 39)37 or with anhydrides (Eq. 40)38 to give benzo[e]quinolizin-l-ones. 

CIC The basic acid taste results from high levels of oxalic and succinic acid. (Z)-3-hexenol and (E)-2-hexenal contribute to the unripe, green aspect and ethyl benzoate with methyl-2-hydroxybenzoate are the typical medicinal notes. Quinoline and ethyl nicotinate add the earthy background. 

Schriever C, Barbatti M, Stock K, Aquino AJA, Tunega D, Lochbmnner S, Riedle E, de Vivie-Riedle R, Lischka H (2008) The interplay of skeletal deformations and ultrafast excited-state intramolecular proton transfer experimental and theoretical investigation of 10-hydroxybenzo[h]quinoline. Chem Phys 347 446... 

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