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.