Efficient Synthesis of Chiral Trisubstituted 1,2-Allenyl Ketones by Catalytic Asymmetric Conjugate Addition of Malonic Esters to Enynes

• Published in: Angewandte Chemie International Edition Vol. 55; no. 5; pp. 1859 - 1863
• Main Authors: Yao, Qian, Liao, Yuting, Lin, Lili, Lin, Xiaobin, Ji, Jie, Liu, Xiaohua, Feng, Xiaoming
• Format: Journal Article
• Language: English
• Published: WEINHEIM Blackwell Publishing Ltd 26.01.2016; Wiley; Wiley Subscription Services, Inc; John Wiley and Sons Inc
• Edition: International ed. in English
• Subjects: 1,2-allenyl ketones; 2-allenyl ketones; 5-hydroxypyrazoline; asymmetric catalysis; Bioactive compounds; Biological activity; Catalysis; Chemical synthesis; Chemistry; Chemistry, Multidisciplinary; Communication; Communications; enyne addition; Esters; furans; Ketones; Pharmacology; Physical Sciences; Scandium; Science & Technology; enyne addition; ENANTIOSELECTIVE SYNTHESIS; 2,3-ALLENOATES; asymmetric catalysis; ALLENES; MICHAEL ADDITION; 1,2-allenyl ketones; AMINATION; LIGANDS; ALLENYLSILANES; ALLENOATES; furans; 5-hydroxypyrazoline; AGENTS; DERIVATIVES
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201509455

An N,N′‐dioxide/scandium(III) complex catalyzed, highly efficient conjugate addition of malonic esters to enynes is described. A range of trisubstituted 1,2‐allenyl ketones were obtained in high yields (up to 99 %) with good d.r. (up to 95/5) and excellent ee values (97 %–99 %). Moreover, the products could be easily transformed into chiral furan and 5‐hydroxypyrazoline derivatives, both of which are important skeletons of many biologically active compounds and pharmacologicals. An N,N′‐dioxide/ScIII complex catalyzed conjugate addition of malonic esters to enynes is described. A range of trisubstituted 1,2‐allenyl ketones were obtained in high yields with good d.r. and excellent ee values. Moreover, the products could be easily transformed to pharmacologically important chiral furan and 5‐hydroxypyrazoline derivatives.