Synthesis of Novel Chiral Diazole Derivative Ligands for the Enantioselective Addition of Diethylzinc to Benzaldehyde
- 1 January 1996
- journal article
- Published by American Chemical Society (ACS) in The Journal of Organic Chemistry
- Vol. 61 (25) , 8915-8920
- https://doi.org/10.1021/jo961388c
Abstract
The high-pressure-promoted reaction of epoxides with pyrazoles and imidazoles provided access to a variety of chiral diazole derivative ligands such as 11-23. Furthermore, chiral pyrazoles 26 and 27, which have a primary alcohol side chain, were also prepared from (+)-camphopyrazole 4. Each of these chiral diazole ligands was used for the catalytic enantioselective addition of diethylzinc to benzaldehyde. The best results were obtained for 16 and 18: 93% ee was achieved in both cases, and reversed asymmetric induction was observed. A plausible mechanism for this efficient asymmetric induction is offered on the basis of X-ray crystallographic data.Keywords
This publication has 13 references indexed in Scilit:
- High-Pressure Organic Chemistry. 19. High-Pressure-Promoted, Silica Gel-Catalyzed Reaction of Epoxides with Nitrogen Heterocycles1,The Journal of Organic Chemistry, 1996
- Highly practical, enantiospecific synthesis of the cyclohexyl fragment of the immunosuppressant FK-506The Journal of Organic Chemistry, 1992
- Enantioselective Addition of Organometallic Reagents to Carbonyl Compounds: Chirality Transfer, Multiplication, and AmplificationAngewandte Chemie International Edition in English, 1991
- High-pressure organic chemistry. 10. Novel neutral alkylations of indoles and pyrroles with vinyl epoxides at high pressureThe Journal of Organic Chemistry, 1990
- Asymmetric Synthesis Utilizing External Chiral LigandsSynthesis, 1990
- Enantioselective addition of dialkylzincs to aldehydes promoted by chiral amino alcohols. Mechanism and nonlinear effectJournal of the American Chemical Society, 1989
- The Coordination Chemistry of Pyrazole‐Derived LigandsPublished by Wiley ,1986
- Interactions of histidine and other imidazole derivatives with transition metal ions in chemical and biological systemsChemical Reviews, 1974
- Coordination chemistry of pyrazole-derived ligandsChemical Reviews, 1972
- Dimethyloxosulfonium Methylide ((CH3)2SOCH2) and Dimethylsulfonium Methylide ((CH3)2SCH2). Formation and Application to Organic SynthesisJournal of the American Chemical Society, 1965