Study of a new 'chiral proton' organocatalyst with hydrolase activity: application in azlactone racemic dynamic resolution. Issue 6 (15th June 2017)

• Record Type: Journal Article
• Authors: Fuentes de Arriba, Ángel L.; Rubio, Omayra H.; Simón, Luis; Alcázar, Victoria; Monleón, Laura M.; Sanz, Francisca; Morán, Joaquin R.
• Is Part Of: Tetrahedron, asymmetry. Volume 28:Issue 6(2017)
• Page Start: 819
• Page End: 823
• Publication Date: 2017-06-15
• Subjects: Asymmetry (Chemistry) -- Periodicals; 547.005
• DOI: 10.1016/j.tetasy.2017.04.012
• Languages: English
• ISSNs: 0957-4166

Abstract

Graphical abstract: A 1, 3-ketoenol system has been studied as an acid catalyst with hydrolytic activity and used for the first time to carry out azlactone racemic mixture resolution. Abstract: For the first time, a 1, 3-ketoenol system is described as an acid catalyst with hydrolytic activity. The combination of an enol and a pyridine/benzimidazole supported on a benzofuran skeleton allowed the creation of a novel bifunctional organocatalyst, which has been applied in azlactone racemic dynamic resolution. In spite of the moderate enantioselectivities obtained, the catalyst constitutes a novel concept in the field of chiral Brønsted acid catalysis. Abstract : 8-Bromo-4-hydroxy- N -(6-methylpyridine-2-yl)-2-oxo-1, 2, 4a, 9b-tetrahydrodibenzo[ b, d ]furan-4a-carboxamide: C19 H15 BrN2 O4 [ α ]D 20 = +142.4 ( c 1.22, CHCl3 ) Absolute configuration: (4a S, 9b R ) Source of chirality: racemic resolution by crystallization Abstract : N -(1 H -Benzo[ d ]imidazol-2-yl)-8-bromo-4-hydroxy-2-oxo-1, 2, 4a, 9btetrahydrodibenzo[ b, d ]furan-4a-carboxamide: C20 H14 BrN3 O4 [ α ]D 20 = +205.6 ( c 0.98, CH3 OH) Absolute configuration: (4a S, 9b R ) Source of chirality: racemic resolution by crystallization