Efficient preparation of nitrosoarenes for the synthesis of azobenzenes.
[reaction: see text] Reaction conditions are described for the oxidation of anilines furnishing nitrosoarenes and the synthesis of unsymmetrically substituted azobenzenes. In a comparative study, the catalytic oxidation of methyl 4-aminobenzoate by hydrogen peroxide was investigated, and SeO(2) proved to be superior or equal to methyl trioxorhenium (MTO) and Na(2)WO(4), respectively. Nevertheless, the application of the inexpensive, environmentally friendly, Oxone in a biphasic system proved to be more efficient, and a variety of useful nitrosoarenes for the synthesis of azo compounds were prepared in high yield and purity on a large scale.
Priewisch
Beate
B
Technische Universität Berlin, Institut für Chemie, Strasse des 17. Juni 135, D-10623 Berlin, Germany.
Rück-Braun
Karola
K
D001391:Azo Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D009603:Nitroso Compounds / Q000138:chemical synthesis*
D001391:Azo Compounds; D009603:Nitroso Compounds; C009850:azobenzene