On hydrogen bonding in the intramolecularly chelated tautomers of enolic malondialdehyde and its mono- and dithio-analogues

Abstract

The intramolecular hydrogen bondings in enolic malondialdehyde and it mono- and dithio-analogues have been evaluated by a semiempricial SCF–MO–CNDO method. The calculations predict that the hydrogen bonds play an important part in the stabilities of malondialdehyde and monothiomalondialdehyde, whereas dithiomalondialdehyde hardly exists as a hydrogen-chelated tautomeric form.