8-alkoxy-5-chloroquinoline

Another chromophore, 8-alkoxy-5-chloroquinoline, was appended to the narrower rim of a calix[4]arene triamide, 44a and 44b (see fig. 38). If Nd111, Er111, and Ybm nitrates are added to acetonitrile solutions of these receptors, quenching of the methoxy quinoline luminescence oc-... 

Sets of homo- and hetero-nuclear substituent constants for the alkoxy-dechlorination of 4-chloroquinolines have been recently obtained from preliminary values of the p-constants and can be extended and improved on the basis of the more extensive data now available. A detailed discussion on substituent constants would extend beyond the scope of this review. In general, it can be stated that unless enhanced resonance interaction occurs with the reaction center in the transition state (i.e., para-, cata-, amphi-N02 groups) or with the aza... 

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. 

Deactivation in the anion formed under the reaction conditions prevents alkoxy-dechlorination of 4-chloro-2-quinolone (222) with boding alkoxide solution while 4-chloroquinoline and its 2-ethoxy and 2-anilino derivatives react. 4-Chloro-iV -methyl-2-quinolone reacts readily. 

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