A study of 2‐aminofurans

Catalytic reduction of 2‐nitrofurans 2 gives low yields of 2‐aminofurans 1 which are not isolated but are trapped using ethyl ethoxymethylenecyanoacetate ( 6 ) or ethoxymethylenemalononitrile ( 7 ). In these reactions 2‐aminofuran ( 1a ) behaves like a dieneamine with substitution occurring at position 5 of the ring. When the 5‐position is substituted reaction takes place at position 3 and thermal cyclisation of the product gives furo‐[2,3‐ b ]pyridine derivatives 16 . An AM1 calculation of the properties of 2‐aminofuran ( 1a ) is reported and the results are consistent with observed properties.