Synthesis of heterocyclic compounds using amidines as their ene-1,1-diamine tautomers. II. Synthesis of 2,3-dihydropyridine, 3,4-dihydropyridine and 3,4-dihydropyrrol-2-one derivatives by the reaction of amidines with α, β-unsaturated carbonyl compounds
✍ Scribed by Kunio Ito; Yoshiko Kizuka; Shogo Ihara
- Publisher
- Journal of Heterocyclic Chemistry
- Year
- 2006
- Tongue
- English
- Weight
- 514 KB
- Volume
- 43
- Category
- Article
- ISSN
- 0022-152X
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✦ Synopsis
N-t-Butylacetamidines 1 on heating with methyl vinyl ketone, acrolein or crotonaldehyde gave the 2,3-dihydropyridine derivatives 4, 5 or 6 via N-alkylation of the acetamidines 1. Reaction of amidines 1 with phenyl 1-propenyl ketone, benzalacetone or chalcone gave 3,4-dihydropyridine derivatives 8, 9 or 10. These were obtained by C-alkylation, achieved by Michael addition of the acetamidines 1 as their N,C-tautomers ene-1,1-diamines 1' to , -unsaturated carbonyl compounds, and subsequent cyclodehydration of adducts. Reaction of 1 with ethyl 3-benzoylacrylate gave 3,4dihydropyrrol-2-one derivatives 13.
📜 SIMILAR VOLUMES
N-t-Butylacetamidines 1 on heating with methyl acrylate (2) at 200˚ gave the 4,5-dihydro-3H-pyridin-2one derivatives 5. Michael addition of the acetamidines 1 as their ene-1,1-diamine tautomers 1' to 2 and the subsequent cyclization of the adducts gave derivatives 5. Amidines 1 on reaction with trim