Control of N‐Heterocyclic Carbene Catalyzed Reactions of Enals: Asymmetric Synthesis of Oxindole‐γ‐Amino Acid Derivatives. (5th December 2017)

• Record Type: Journal Article
• Authors: Chen, Xiang‐Yu; Xiong, Jia‐Wen; Liu, Qiang; Li, Sun; Sheng, He; von Essen, Carolina; Rissanen, Kari; Enders, Dieter
• Is Part Of: Angewandte Chemie. Volume 130:Number 1(2018)
• Page Start: 306
• Page End: 310
• Publication Date: 2017-12-05
• Subjects: Asymmetrische Synthesen -- Carbene -- Cycloadditionen -- Lactame -- Oxindole; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201708994
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: A strategy to control the switch between a non‐cycloaddition reaction and a cycloaddition reaction of enals, using N‐heterocyclic carbene (NHC) catalyisis, has been developed. The new scalable protocol leads to γ‐amino‐acid esters bearing a tetrasubstituted stereocenter in good yields and high stereoselectivities by homo‐Mannich reactions of enals and isatin‐derived ketimines. By simply changing the N‐ketimine substituent to an ortho ‐hydroxy phenyl group, the corresponding spirocyclic oxindolo‐γ‐lactams are obtained.