Ionic and Covalent Copper(II)-Based Catalysts for Michael Additions. The Mechanism

• Published in: Journal of organic chemistry Vol. 69; no. 20; pp. 6834 - 6842
• Main Authors: Comelles, Josep, Moreno-Mañas, Marcial, Pérez, Elisabet, Roglans, Anna, Sebastián, Rosa M, Vallribera, Adelina
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 01.10.2004; Amer Chemical Soc
• Subjects: Catalysis; Catalysts: preparations and properties; Chemistry; Chemistry, Organic; Exact sciences and technology; General and physical chemistry; Kinetics and mechanisms; Organic chemistry; Physical Sciences; Reactivity and mechanisms; Science & Technology; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; TRANSITION-METAL CATALYSIS; ORGANIC-SYNTHESIS; CARBON; 1,3-DICARBONYL COMPOUNDS; COMPLEXES; QUATERNARY STEREOCENTERS; BETA-KETO-ESTERS; IONIZATION MASS-SPECTROMETRY; CONJUGATE ADDITIONS; DICARBONYLS; Michael addition; Copper II; Catalytic reaction; Ionic compound; Diketone; Experimental study; Electrospray; Infrared spectrometry; Neutral medium; Copper Organic compounds; Reaction mechanism; Ketoester; Covalent complex; Enolate; Mass spectrometry; Catalyst; Nucleophile; Ultraviolet visible spectrometry
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo049373z

Cu(SbF6)2-AdamBox and copper(II) bis-(5-tert-butylsalicylaldehydate) catalyze the Michael addition in neutral media. Mechanistic studies, based on UV−vis, IR, and electrospray ionization mass spectrometry (ESI-MS), suggest that copper enolates of the β-dicarbonyl formed in situ are the active nucleophilic species.