Collect. Czech. Chem. Commun. 1984, 49, 2613-2619

Vinylogues and heterocyclic analogues of benzylidenemalonaldehydes

Zdeněk Arnold, Dalimil Dvořák and Vladimír Král

Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Prague 6


Nine analogues of benzylidenemalonaldehyde (IV) were prepared by condensation of bis(dimethylamino)trimethinium perchlorate with two vinylogues of benzaldehyde and a series of heterocyclic aldehydes. The reaction intermediate was isolated and shown by 1H NMR spectroscopy to be the bis-iminium salt III. The conformation of 3-phenylprop-2-enylidenemalonaldehyde (IVa), determined by its 1H NMR spectrum, may serve as a more general model of arylmethylenemalonaldehydes.