Olefins alkylations, quinoline

A range of secondary A-alkylanilines undergo oxidative olefination with 2-alkyl-quinoline, 4-methylquinoline, 1-methylisoquinoline, 2-methylquinoxaline, 2-methyl-quinazoline, 2-methylbenzo[fiG-thiazole, acetophenone, and malononitrile in DMF to form structurally diverse polysubstituted alkenes in moderate to excellent yields with excellent E Z >99 1 selectivity with the use of 2,3-dichloro-5,6-dicyano-l,4-benzoquinone as the oxidant. Mechanistically, the oxidative olefination reaction proceeds through amine oxidation followed by imine olefination." ii... 

HETE (138) is known to inhibit 5-LO [334]. A group at Revlon created a series of combined 5-LO inhibitors/LT antagonists derived conceptually from the structure of 15-HETE. REV 5901A (139) [335], the best of the series, inhibited 5-HETE release from rat ISN (0.12 //M) and was fairly selective with respect to CO and 12-LO inhibition. The quinoline could be replaced by another lipophilic aromatic group, but potency decreased (naphthalene was 40-fold less potent, and substituted phenyl was 5- to 20-fold less active). Pyridines were active but also less potent 2-pyridyl was only 4-fold less active, while 3- and 4-pyridyl were 20-fold weaker. Ortho-and pnra-substituted phenylene groups were less active. Elimination of the side-chain hydroxyl to the olefin caused a loss of activity, as did the use of shorter alkyl chains. 

Primary halides are more reactive than secondary compounds quaternary salt formation does not occur with tertiary halides, elimination always occurring to give the hydriodide and an olefin. Also, the larger the alkyl group the slower is the reaction this is shown by the very slow reaction of dodecyl bromide with quinoline, and even butyl iodide is much slower to react than methyl iodide. The longer chain primary halides commonly undergo elimination rather than cause quatemization for example, n-octyl and cetyl iodides give only the hydriodides when heated with 9-aminoacridine. ... 

Alkylation. Alkylation of the 2-position of quinoline is possible via C-H activation. Using rhodium catalysis, olefins can... 

Terminal acetylenes are often used as precursors to the E- and Z-olefins. A typical synthesis is that reported by Schwarz and Waters (187) (Scheme 80). The alkali metal salt of the acetylene is coupled with an appropriate alkyl halide to give the acetylenic tetrahydropyranyl ether (444). Sodium in liquid ammonia reduction of the ether stereo-specifically affords.pure -olefins, which can be hydrolyzed to an alcohol and then acetylated. For Z-isomers, the protecting group must first be removed and the alcohol acetylated. Reduction over quinoline-poisoned... 

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