Effect of metal ions in organic synthesis. Part XV. Reaction of (arylazo) alkenes and copper(II) chloride in dienophiles or acetone. Synthesis of some N-(α-chlorobenzylidene)-N′ -arylhydrazines

Abstract

The reaction of (phenylazo) stilbene and copper(II) chloride wih some dienophiles produced benzaldehyde and N-(α-chlorobenzylidene)-N′-phenylhydrazine, instead of the expected (4+2)-cycloaddition products. By reaction of some (arylazo) alkenes and copper(II) chloride in acetone at 0 °C, the relative N-(α-chlorobenzylidene)-N′-arylhydrazine derivatives were successfully obtained in high yields.