Dependent on the reaction time, the three-component condensation
of dimethyl acetonedicarboxylate (1), aromatic
aldehydes 2, and malononitrile (3) gives rise to 4H-pyran
derivatives 5 after reflux for 15 min.
Moreover, using excess of benzaldehyde and prolonged heating for
150 min afforded multifunctional cyclohexanone derivatives 8. Different substitution patterns in the
phenyl nucleus of 8 can be achieved by
condensation of 4H-pyran derivatives 5 with benzaldehydes 2.
heterocycles - carbocycles - Michael additions - rearrangements - cyclizations - condensation
