Lewis acid-promoted cyclization/halogenation of allenyl ethenetricarboxylates and the corresponding amides: stereoselective synthesis of haloalkenyl five-membered heterocyclesElectronic supplementary information (ESI) available: The optimized geometries, and 1H and 13C NMR spectral data. See DOI: 10.1039/c4ob00233d

• Main Authors: Fukushima, Yugo, Yamazaki, Shoko, Ogawa, Akiya
• Format: Journal Article
• Language: English
• Published: 21.05.2014
• ISSN: 1477-0520; 1477-0539
• DOI: 10.1039/c4ob00233d

Lewis acid-promoted intramolecular reactions of allenyl ethenetricarboxylates and the corresponding amides have been examined. Reactions of allenyl ethenetricarboxylates and the amides with Lewis acids such as AlCl 3 , AlBr 3 and ZnX 2 (X = Cl, Br, I) gave 3,4- trans haloalkenyl five-membered heterocycles stereoselectively. The stereochemistry was determined by NOE experiments and reduction of the cyclized products. Various transformations of the haloalkenyl functionalized cyclic compounds have also been performed. Lewis acid-promoted intramolecular reactions of allenyl ethenetricarboxylates and the corresponding amides gave 3,4- trans haloalkenyl five-membered heterocycles stereoselectively. Transformations of the products utilizing the haloalkenyl functionality have been demonstrated.