Synthesis of bis(azafulvene)s by dehydration of hydroxymethylpyrrole derivatives.
Bis(azafulvene) was isolated in 55% yield by the reaction of 4 equivalents of phenyllithium with 5,5'-diformyl-3,3',4,4'-tetraethyl-2,2'-bipyrrole followed by quenching with acetic anhydride. Unstable bis(azafulvene)s were obtained in much higher yields by dehydrating 5,5'-bis(hydroxymethyl) derivatives of 2,2'-bipyrrole and gem-dimethyl-2,2'-dipyrrylmethane with (Boc)2O-DMAP at room temperature. X-Ray crystallography of two bis(azafulvene)s is reported.
Setsune
Jun-ichiro
J
Department of Chemistry, Faculty of Science, Kobe University, Nada-ku, Kobe 657-8501, Japan. setsunej@kobe-u.ac.jp
Tanabe
Aya
A
Watanabe
Junko
J
Maeda
Satoshi
S