the direct intramolecular addition of aldehydes to non-activated alkynes. Accordingly, the carbocyclizations of a range of formyl-alkynes afforded the corresponding cyclopentanes in good to excellent yields. Experimental evidence tends to support a synergistic enamine/π-activation reaction mechanism. The fruitful merger of iron catalysis to amine catalysis was successfully applied in the direct intramolecular
Cooperative Copper(I) and Primary Amine Catalyzed Room-Temperature Carbocyclization of Formyl Alkynes
作者:Benjamin Montaignac、Maxime R. Vitale、Virginie Ratovelomanana-Vidal、Véronique Michelet
DOI:10.1002/ejoc.201100464
日期:2011.7
An efficient CuI/amine catalytic system is described for the carbocyclization of α-disubstituted formylalkynes at room temperature. Merging aminocatalysis to the copper(I)-catalyzed activation of alkynes led to clean carbocyclization of a wide range of functionalized substrates under mild conditions. This novel cooperative catalytic system allowed the formation of a variety of carbo- and heterocycles
DFT-assisted design and evaluation of bifunctional copper(I) catalysts for the direct intermolecular addition of aldehydes and ketones to alkynes
作者:Jacob D. Porter、Eric Greve、Abdulmohsen Alsafran、Adam R. Benoit、Sergey V. Lindeman、Chris Dockendorff
DOI:10.1016/j.tet.2018.07.034
日期:2018.9
structures of the designed catalysts were computed using density functional theory (DFT), and the relative energies of putative catalytic intermediates were estimated and used to prioritize catalyst designs. Novel bifunctional precatalysts containing a thiazole spacer were synthesized via a 9-step sequence and combined with transition metals before screening for the direct addition of aldehydes and ketones
Enantioselective metallo-organocatalyzed preparation of cyclopentanes bearing an all-carbon quaternary stereocenter
作者:Benjamin Montaignac、Chandrasekaran Praveen、Maxime R. Vitale、Véronique Michelet、Virginie Ratovelomanana-Vidal
DOI:10.1039/c2cc32823b
日期:——
Enantioselective metallo-organocatalyzed carbocyclizations of formyl-alkynes have been developed. The cooperation between aminocatalysis and a chiral copper(I) complex granted access to enantio-enriched cyclopentanes through the challenging formation of all-carbon quaternary stereocenters.
Enantioselective Merger of Aminocatalysis with π-Lewis Acid Metal Catalysis: Asymmetric Preparation of Carbo- and Heterocycles
作者:Chandrasekaran Praveen、Benjamin Montaignac、Maxime R. Vitale、Virginie Ratovelomanana-Vidal、Véronique Michelet
DOI:10.1002/cctc.201300313
日期:2013.8
ratio. After a careful examination of several other strategies, the best synergic catalytic system, which combines a chiral copper(I) complex with cyclohexylamine, afforded the enantioselective preparations of cyclopentane, indane, and pyrrolidine scaffolds with moderate to excellent control of the all‐carbon quaternary stereogenic centers created through such cyclization processes.