Development of a new acid-base bifunctional asymmetric organocatalyst and its utilization

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beta-ICD is the versatile catalyst utilized for various organocatalytic asymmetric reactions represented by the Morita-Baylis-Hillman (MBH) reaction. However, the enantiomer of beta-ICD is not easily available. In this research we have developed a new cinchona alkaloid-derived catalyst, alpha-ICPN, which is available in 90% yield in one step from quinine. alpha-ICPN effectively catalyzed MBH reactions in high and opposite enantioselectivity to that observed for the beta-ICD-catalyzed reactions. In addition, one derivative of alpha-ICPN catalyzed aza-version of MBH reactions in high enantioselectivity. These results suggest that alpha-ICPN can be utilized as an enantiocomplementary catalyst of beta-ICD. Furthermore, we have developed a new methodology for the construction of polypropionate structures by taking advantage of both beta-ICD and alpha-ICPN-catalyzed MBH reactions.