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

ABSTRACT: 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.

SUBMITTER: Yao Q

PROVIDER: S-EPMC4738401 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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

Yao Qian Q Liao Yuting Y Lin Lili L Lin Xiaobin X Ji Jie J Liu Xiaohua X Feng Xiaoming X

Angewandte Chemie (International ed. in English) 20151222 5

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. ...[more]

PMID: 26694204

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