2.5- Cyclohexadienone anilines

The basic principle of all diazotizations of aromatic amines with a hydroxy- or a sulfonamido group in the 4-position relative to the amino group involves a deprotonation of the OH or NH group, respectively, after diazotization of the amino group. There is also a case of a deprotonation of a CH group in the 4-position of an aniline derivative, namely in the diazotization of 4-aminophenylmalononitrile (2.41) which, by the sequence of steps shown in Scheme 2-23, yields 3-diazo-6-dicyanomethylene-1,4-cyclohexadienone (2.42), as found by Hartzler (1964). This product can also be represented by a zwitterionic carbanion-diazonium mesomeric structure. 

Arylamino)-cyclohexadienones (21) rearrange in acid solution (often in alcohol or acetic acid solvents) to give 4-(aryloxy)-anilines (22) (Scheme 6). In some ways this... 

Spiro benzodioxole-cyclohexadienones have been prepared from 4-(2-hydroxyphenoxy)anilines by oxidation using 5 equiv of manganese dioxide (Equation 50) <1997TL5563>. 

Silver trifluoroacetate 4-Alkoxy-2,5-cyclohexadienone imines from anilines... 

The cyclohexadienone (imine) tautomers of 0- and p-halophenols (and anilines) are most likely the reactive species during their dehalogenation (27) at elevated temperatures. 

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