Study on the scope of tert-amino effect: new extensions of type 2 reactions to bridged biaryls~?

摘要

Thermal isomerization of aminomethyl-or oxygen-bridged biphenyl systems possessing dicyanovinyl and sec-amino groups in ortho- and ortho'-positions was investigated. Both systems underwent cyclization via tert-amino effect. Thus, 2-(2-{[2-(sec-amino)benzyl]-N-methylamino)benzylidene)malononitriles gave tetrahydroquinolines, whereas a 2-[2-(sec-amino)phenoxy]benzylidenemalononitrile isomerized to dibenzoxazonine derivative. The ring closure reaction was studied by differential scanning calorimetry measurements.