Enantioselective organocatalyzed cascade reactions to highly functionalized quinolizidines

• Published in: Tetrahedron Vol. 67; no. 17; pp. 3034 - 3040
• Main Authors: Dai, Xiaoyang, Wu, Xiaoyu, Fang, Huihui, Nie, Linlin, Chen, Jie, Deng, Hongmei, Cao, Weiguo, Zhao, Gang
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 29.04.2011; Elsevier
• Subjects: Cascade; Chemistry; Chemistry, Organic; Cyclization; Exact sciences and technology; Heterocyclic compounds; Heterocyclic compounds with several n hetero atoms in the same ring, in separated rings or in fused rings; Organic chemistry; Organocatalysis; Physical Sciences; Preparations and properties; Quinolizidine; Science & Technology; KHZVPEGYYMRMIZ-LKQVSLMWSA-N; Cyclization; Organocatalysis; Cascade; Quinolizidine; ALKALOID SYNTHESIS; (+)-GEISSOSCHIZINE; DOMINO REACTIONS; ALPHA,BETA-UNSATURATED ALDEHYDES; N-ACYLIMINIUM IONS; CATALYTIC CYCLIZATION; STEREOCENTERS; CONSTRUCTION; INDOLE ALKALOIDS; DERIVATIVES; Michael addition; One pot reaction; Catalytic reaction; Ketoamide; Configuration; Enantioselectivity; Nitrogen heterocycle; Enol; Aldehyde; Unsaturated compound; Benzoquinolizine derivatives; Functionalization; Aromatic compound; Catalysis; Pictet Spengler reaction; Successive reaction
• ISSN: 0040-4020; 1464-5416
• DOI: 10.1016/j.tet.2011.03.007

An organocatalyzed one-pot Michael addition-Pictet–Spengler sequence of β-ketoamides and α,β-unsaturated aldehydes was developed, which provided access to highly substituted indolo[2,3-α]quinolizidines and benzo[α]quinolizidines in moderate to good yields and good to excellent enantioselectivities. For aromatic α,β-unsaturated aldehydes 1a– j products 10a– r containing a stable enol configuration were obtained. [Display omitted]