Quinoline- 7-chloro-4-ethoxy

Indirect deactivation by an alkoxy group is apparent in the sluggish reaction of 4-butoxy-2-chloroquinoline with w-butylamine (EtOH, 5 hr, 180°, but not at 80°). The chloro group in 2-chloro-4-ethoxy-quinoline is more reactive than that in the 4-chloro-2-ethoxy isomer toward alkoxides or amines in spite of the usually more effective para indirect deactivation in the former. For kinetic data on quinolines see Tables X and XI, pp. 336 and 338, respectively. 

Reaction of 2,4,7-trichloroquinoline with sodium methoxide (65°, 30 min) yielded an equal mixture of 2,7-dichloro-4-methoxy- (40%) and 4,7-dichloro-2-methoxy-derivatives (31%). The activating effect of the chloro groups is evident from the inertness of 4-chloro-quinoUne to methoxide ion at 65°. Alteration of the relative reactivity by cationization of the azine ring is again noted here in the acid-catalyzed hydrolysis (dilute HCl, 100°, 1.5 hr) of the trichloro compound to give 72% of the 2-hydroxylation product.Similarly, acid-hydrolysis of the alkoxy group proceeds much more readily in 2-ethoxy-4-chloro- than in 4-ethoxy-2-chloro-quinoline. ... 

Ethoxyacetylene, 133, 190, 270 N-Ethoxycarbonyl-2-ethoxy-1,2-dihydro-quinoline (EEDQ), 191 Ethoxycarbonylhydrazine, 191 2-Ethoxy-3-chloro-l,3-cycloheptadiene, 350... 

Very mobile nitro groups can be replaced directly by chlorine or bromine, a reaction that has preparative importance for bromo- and chloro-pyridine and -quinoline derivatives. 5-Ethoxy-2-nitropyridine gives 2-bromo-5-ethoxy-pyridine when heated with HBr in glacial acetic acid in a sealed tube for 3 hours at 130°,1260 and 2-bromo-3-ethoxypyridine is obtained from the corresponding nitro compound and boiling 48% HBr.1261 It is particularly easy to introduce Cl or Br in place of a 4-nitro group in pyridine 1-oxide or quino-... 

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