3- quinoline preparation

Trimethyloxazolo[4,5-/]quinoline prepared from 2,7-dimethyl-6-methoxyquinoline using nitration, demethylation (or reversed), reduction, and cy-clization with acetic anhydride confirms unambigously the structure of the aromatic part of the antibiotic X-537A after nitration and alkaline degradation (71JOC3621). 

Amino group of 3-(4-aminobutyl)-2,3,4,4u,5,6-hexahydro-l//-pyrazino [l,2-u]quinoline, prepared from 3-[4-phthalimidobutyl) derivative by treatment with H2NNH2 H2O in boiling EtOH, was acylated with 2-fluorenecarbonyl chloride in the presence of NEt3 in CHCI3 (97MIP12). 

Some of the quinoline preparations based on intramolecular SeAt processes belong to the classics of heterocycle synthesis. For instance, primary arylamines with a free ortho position can be made to undergo cyclocondensation with (3-diketones or with p-keto aldehydes in a strongly acidic medium Combes synthesis [101]) ... 

Table V. Wheat Powdery Mildew Control of Modified 4-(4-Fluorophenoxv -quinolines Prepared in Modification C...

Metal-catalysed amine dehydrogenation has been utilised for quinoline preparation. Shim and Cho have reported the union of 2-amino ben l alcohol with secondary alcohols in the presence of catalytic RuCl2(PPh3)3 at 80 °C to afford quinolines (Scheme 12.40). The mechanism may involve transfer of hydrogen from both alcohol reactants to dodecene (a sacrificial hydrogen acceptor) to provide the corresponding carbonyls. In the absence of dodecene, only trace product is formed evaluation of other hydrogen acceptors was not described. KOH-induced aldol condensation followed by cyclodehydration would provide the observed quinolines. 

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