Novel (2-amino-4-arylimidazolyl)propanoic acids and pyrrolo[1,2-c]imidazoles via the domino reactions of 2-amino-4-arylimidazoles with carbonyl and methylene active compounds

• Victoria V. Lipson,
• Tetiana L. Pavlovska,
• Nataliya V. Svetlichnaya,
• Anna A. Poryvai,
• Nikolay Yu. Gorobets,
• Erik V. Van der Eycken,
• Irina S. Konovalova,
• Svetlana V. Shiskina,
• Alexander V. Borisov,
• Vladimir I. Musatov and
• Alexander V. Mazepa

Beilstein J. Org. Chem. 2019, 15, 1032–1045, doi:10.3762/bjoc.15.101

• considered as the analogues of both 3,3’-spirooxindole and 2-aminoimidazole marine sponge alkaloids. Keywords: 2-amino-4-arylimidazole; (2-amino-4-arylimidazolyl)propanoic acid; isatin; Meldrum’s acid; multicomponent reactions; pyrrolo[1,2-c]imidazole; 3,3’-spirooxindoles; Introduction Heterocyclic

• -1,3-dioxin-4-ones: An equimolar mixture (1.0 mmol) of the corresponding 2-amino-4-arylimidazole 1, aromatic aldehyde 2 and Meldrum’s acid 3 was refluxed in iPrOH (3 mL) for 3–5 min. After cooling, the solid products 4 were filtered off, washed with iPrOH and dried on air. 4a: colourless solid, 77%; mp

• ]imidazole-6-carboxylates. A mixture of the corresponding 2-amino-4-arylimidazole 1 (1.0 mmol), aromatic aldehyde 2 (2.0 mmol) and ethyl 2-cyanoacetate 15 (1.0 mmol) in 2 mL of 2-propanol was refluxed during 20–30 min. After cooling, the yellow solid products 16 were filtered off and crystallized from iPrOH