Highly enantioselective synthesis of γ-, δ-, and ε-chiral 1-alkanols via Zr-catalyzed asymmetric carboalumination of alkenes (ZACA)–Cu- or Pd-catalyzed cross-coupling
| Autor: | Shiqing Xu, Akimichi Oda, Hirofumi Kamada, Ei-ichi Negishi |
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| Rok vydání: | 2014 |
| Předmět: |
Stereoisomerism
Alkenes Catalysis chemistry.chemical_compound polycyclic compounds Organic chemistry heterocyclic compounds Aluminum Compounds Alkyl chemistry.chemical_classification Multidisciplinary Molecular Structure organic chemicals Aryl Synthon Enantioselective synthesis Absolute configuration Acetylation Lipase Carbon Models Chemical chemistry Alcohols Physical Sciences Zirconium Enantiomer Oxidation-Reduction Copper Palladium |
| Zdroj: | Proceedings of the National Academy of Sciences. 111:8368-8373 |
| ISSN: | 1091-6490 0027-8424 |
| Popis: | Despite recent advances of asymmetric synthesis, the preparation of enantiomerically pure (≥99% ee) compounds remains a challenge in modern organic chemistry. We report here a strategy for a highly enantioselective (≥99% ee) and catalytic synthesis of various γ- and more-remotely chiral alcohols from terminal alkenes via Zr-catalyzed asymmetric carboalumination of alkenes (ZACA reaction)-Cu- or Pd-catalyzed cross-coupling. ZACA-in situ oxidation of tert-butyldimethylsilyl (TBS)-protected ω-alkene-1-ols produced both (R)- and (S)-α,ω-dioxyfunctional intermediates (3) in 80-88% ee, which were readily purified to the ≥99% ee level by lipase-catalyzed acetylation through exploitation of their high selectivity factors. These α,ω-dioxyfunctional intermediates serve as versatile synthons for the construction of various chiral compounds. Their subsequent Cu-catalyzed cross-coupling with various alkyl (primary, secondary, tertiary, cyclic) Grignard reagents and Pd-catalyzed cross-coupling with aryl and alkenyl halides proceeded smoothly with essentially complete retention of stereochemical configuration to produce a wide variety of γ-, δ-, and ε-chiral 1-alkanols of ≥99% ee. The MαNP ester analysis has been applied to the determination of the enantiomeric purities of δ- and ε-chiral primary alkanols, which sheds light on the relatively undeveloped area of determination of enantiomeric purity and/or absolute configuration of remotely chiral primary alcohols. |
| Databáze: | OpenAIRE |
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