Sequential Gold and Organocatalyzed Bicyclization for Asymmetric Construction of Contiguous Tetrasubstituted Carbon
Jie Wang1, Yi Gao1, Xin-Zhe Niu1
1Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education, Key Laboratory of Pharmaceutical Quality Control of Hebei Province, College of Pharmaceutical Sciences, Hebei University, Baoding 071002, China.
Abstract:
Employing a sequential gold and organocatalytic system, we have achieved a one-pot double annulation of versatile 1,3-dicarbonyl compounds bearing a 3-butynoic acid moiety. This process proceeds through a gold-catalyzed 5-endo-dig cyclization, followed by a thiourea-catalyzed intramolecular vinylogous aldol reaction. By strategically employing desymmetrization and dynamic kinetic resolution, respectively, this methodology enables the efficient and asymmetric construction of a series of spiro-butenolide architectures incorporating contiguous tetrasubstituted carbon stereocenters.
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