Alkoxy-nitro

Since various substituents are tolerated, the Friedlander reaction is of preparative value for the synthesis of a large variety of quinoline derivatives. The benzene ring may bear for example alkyl, alkoxy, nitro or halogen substituents. Substituents R, R and R" also are variable. The reaction can be carried out with various carbonyl compounds, that contain an enolizable a-methylene group. The reactivity of that group is an important factor for a successful reaction. 

Compounds with Reactive Methylene Groups. In this group the coupling components with the greatest industrial importance are the A-acetoacetyl derivatives of aromatic amines (acetoacetarylides) CH3COCH2CONHAr. Anilines substituted by halogen, alkyl, alkoxy, nitro, and acylamino groups are most suitable (e.g., Napthol AS-IRG). 

In like manner the higher homologues or mixed alkoxy-derivatives of phenyl ethyl amine may be made by reducing the corresponding 3,4,5-alkoxy-nitro-styrenes, that is to say such as contain higher or mixed alkoxy-groups. 

Laccase can be used to catalyze the oxidation of aromatic methyl or methylol groups to the corresponding aldehydes (where R = Cl, alkoxy, nitro) by oxygen in the presence of a benzothiazoline compound (9.12).158... 

Ciba Geigy 1981 R, R2 saturated or unsaturated alkyl,cycloalkyl R3 Halogen, alkoxy, nitro,CF3 n 0-3... 

Nucleophilic substitution occurs through similar intermediates when the aromatic ring contains a potential leaving group. The most common case involves displacement of halide, but alkoxy, nitro and cyano groups can also be displaced by the addition-elimination mechanism. It is noteworthy that leaving-group ability... 

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