Solvent-free, one-pot synthesis of polyhdroquinoline and 1,8-dioxodecahydroacridine derivatives have been described via Hantzsch condensation of various aldehydes, ammonium acetate with (i) cyclic 1,3-dicarbonyl compounds and ethyl acetoacetate and (ii) cyclic 1,3-dicarbonyl compounds (2 mmoles) in a very simple, efficient, and environmentally benign method using 1,3-(dibromo or dichloro)- 5,5-dimethylhydantoin as a cheap, non-toxic and neutral catalyst with up to excellent yields.
