On the illusive nature of o-formylazobenzenes: exploiting the nucleophilicity of the azo group for cyclization to indazole derivatives.
Facile rearrangement of azobenzenes is shown to occur in cases where the azo group is placed in the ortho position to carbonyl electrophiles to furnish the indazole skeleton. While this study demonstrates the illusive nature of o-formylazobenzenes, it offers potential for the synthesis of indazoles and related heterocycles.
Peters
Maike V
MV
Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
Stoll
Ragnar S
RS
Goddard
Richard
R
Buth
Gernot
G
Hecht
Stefan
S