Enantioselective Friedel-Crafts alkylation of indole with nitroalkenes in the presence of bifunctional squaramide organocatalysts
Tetrahedron Letters, cilt.73, ss.1-4, 2021 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 73
- Basım Tarihi: 2021
- Doi Numarası: 10.1016/j.tetlet.2021.153153
- Dergi Adı: Tetrahedron Letters
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Chimica, EMBASE, Veterinary Science Database
- Sayfa Sayıları: ss.1-4
- Anahtar Kelimeler: Asymmetric synthesis, Organocatalysis, Squaramide organocatalyst, Friedel-Crafts alkylation, Indole, MICHAEL ADDITION, DERIVATIVES, CATALYST
- Açık Arşiv Koleksiyonu: AVESİS Açık Erişim Koleksiyonu
- Orta Doğu Teknik Üniversitesi Adresli: Evet
Özet
© 2021 Elsevier LtdA series of chiral bifunctional quinine and 2-aminoDMAP based squaramide organocatalysts are evaluated in Friedel-Crafts alkylation of indoles with nitroolefins. These 3-substituted indole derivatives are synthesized in the presence of sterically encumbered tert-butyl squaramide/quinine with high enantioselectivity (up to >99% ee) and moderate chemical yields (up to 80%) by representing as chiral precursors for very important biologically active molecules. Besides, this asymmetric transformation provides a very simple, efficient, clean and environmental friendly route. In addition, this process has very mild reaction conditions such as ambient temperature and usage of only 2 mol% catalyst loading compared to previous studies in literature.