2-Amino-4,5-dihydro-3-furancarbonitriles (ADFCs) have attracted much attention due to
their utility as valuable synthetic intermediates for the preparation of a series of acyclic and cyclic organic
compounds. On the other hand, indoles substituted with furans are highly interesting compounds
displaying a wide range of biological and pharmaceutical activities. However, to the best of our knowledge,
indole substituted 2-amino-4,5-dihydro-3-furancarbonitriles have not been previously reported. A
new and efficient synthesis of indole substituted 2-amino-4,5-dihydro-3-furancarbonitriles has been
developed in two steps using water as a solvent. The first step of the sequence involves threecomponent
reaction of phenylglyoxals, indoles and malononitrile under aqueous and catalyst-free conditions
for the synthesis of indole substituted β,β-dicyanoketones. Reduction of the obtained β,β-
dicyanoketones with sodium borohydride in water at room temperature afforded the indole substituted
2-amino-4,5-dihydro-3-furancarbonitriles in good yields. Several substituted phenylglyooxals were reacted
smoothly with indole or 2-methylindole and malononitrile to give the corresponding indole substituted
β,β-dicyanoketones in good yields. Treatment of the obtained β,β-dicyanoketones with sodium
borohydride in water furnished exclusively the indole substituted 2-amino-4,5-dihydro-3-
furancarbonitriles in good yields. We have developed an efficient straightforward access to indole substituted
β,β-dicyanoketones by one-pot three-component reaction of phenylglyoxals, indoles and
malononitrile. The synthetic utility of obtained indole substituted β,β-dicyanoketones has been outlined
by the preparation of indole substituted 2-amino-4,5-dihydro-3-furancarbonitriles. The advantage of
catalyst-free, atom-economical and environmental benignity render it promising methods for preparation
of indole substituted 2-amino-4,5-dihydro-3-furancarbonitriles.
Copper aluminum mixed oxide (CuAl MO) catalyst: A green approach for the one-pot synthesis of imines under solvent-free conditions
