【摘 要】
：
A novel upper-rim functionalized calix[4]squaramide organocatalyst bearing bis-squaramide and cyclohexanediamine scaffolds was designed and prepared to catalyse
【机 构】
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Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology. School of Petrochemical Enginee
论文部分内容阅读
A novel upper-rim functionalized calix[4]squaramide organocatalyst bearing bis-squaramide and cyclohexanediamine scaffolds was designed and prepared to catalyse a serial of asymmetric Michael addition of 1,3-dicarbonyl compounds to α,β-unsaturated carbonyl compounds in high yields (up to 99 ％)and good to excellent enantiomeric excesses (up to 99％ ee). The comparative experiments indicated that the cooperative effect between calixarenes cavitives and chiral catalytic centers on this calix[4]squaramide catalyst could promote these reactions. Moreover, this strategy also provides valuable and easy access to chiral chromene, naphthoquinone and acetylacetone derivatives, which are important skeletons in biological and pharmaceutical compounds.
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