Highly Enantioselective Synthesis of Polysubstituted Tetrahydroquinolines via Organocatalytic Michael/Aza-Henry Tandem Reactions

Asymmetric synthesis of tetrahydroquinolines through supramolecular organocatalysis

Functionalized chiral tetrahydroquinolines were synthesized through supramolecular organocatalysis using quinidine-NH-thiourea 3c/l-phenylalanine 4i followed by reductive amination from the simple substrates.

Facile construction of three contiguous stereogenic centers via dynamic kinetic resolution in asymmetric transfer hydrogenation of quinolines

An efficient and facile route to chiral tetrahydroquinolines with three contiguous stereogenic centers via a dynamic kinetic resolution process has been successfully developed by using chiral phosphoric acid as catalyst and Hantzsch ester as the hydrogen source with up to 89% ee.

Organocatalyzed Michael-Michael cascade reaction: asymmetric synthesis of polysubstituted chromans

An enantioselective cascade Michael-Michael reaction between chalcones enolates and nitromethane catalyzed by a bifunctional thiourea is developed. This reaction provides a mild but efficient approach to chiral benzopyrans bearing three consecutive stereocenters in high yields with excellent stereoselectivities, and the benzopyrans can be easily transformed to the corresponding tricyclic product.

Concise construction of the tetracyclic core of lycorine-type alkaloids and the formal synthesis of α-lycorane based on asymmetric bifunctional thiourea-catalyzed cascade reaction

A concise and stereoselective construction of the tetracyclic core of lycorine-type alkaloids and the formal synthesis of α-lycorane has been achieved. The feature of the current method is the employment of a bifunctional thiourea-catalyzed cascade reaction as a powerful tool to construct the skeleton of the natural product, which is a challenging yet very rarely explored strategy. As a result, the tetracyclic core is efficiently synthesized in just three simple operations involving two consecutive cascade reactions.

Catalytic asymmetric synthesis of chromenes and tetrahydroquinolines via sequential allylic alkylation and intramolecular Heck coupling

Highly enantioselective synthesis of chiral chromenes and tetrahydroquinolines is achieved by combining asymmetric copper-catalyzed allylic substitution with Grignard reagents and an efficient intramolecular Heck reaction. Moreover, the exocyclic double bond formed in the cyclisation was subjected to RCM, hydroboration and hydrogenation illuminating the synthetic versatility of these heterocycles.