One-pot synthesis of spirooxindole-pyrrolizidine compounds using magnetically separable Fe₃O₄-graphene oxide (Fe₃O₄-GO) catalyst

A couple of novel Spirooxindole-pyrrolizidine compounds have been synthesized from chalcone derivatives as α, β-unsaturated carbonyl compounds by the help of heterogeneous magnetically separable Fe3O4-GO catalyst. Four steps involved in this research are synthesis of Fe3O4-GO catalyst, synthesis of chalcone derivatives from 4-hydroxybenzaldehyde and cinnamaldehyde, synthesis of spirooxindole-pyrrolizidine derivatives by 1,3-dipolar-cycloaddition reaction through the formation of azomethine ylide, and the last is antioxidant activity assay using DPPH method. The result showed that the use of Fe3O4-GO catalyst as much as 5 wt% can increase the reaction yield to 86.27 %. From the DPPH assay, it is known that spirooxindole-pyrrolizidine derivatives have an antioxidant activity but spirooxindole-pyrrolizidine derived from 4-hydroxybenzaldehyde is the better one.