An array of natural products bearing chiral peroxide motifs display antitumor,anticancer,and antiparasitic activities.However,there are very few catalytic asymmetric syntheses of chiral peroxides.Moreover,effective ca...An array of natural products bearing chiral peroxide motifs display antitumor,anticancer,and antiparasitic activities.However,there are very few catalytic asymmetric syntheses of chiral peroxides.Moreover,effective catalysts for asymmetric catalytic peroxidations are limited to chiral amines.To further expand synthetic access to chiral peroxides,the development of new catalysts realizing catalytic asymmetric peroxidation is highly desirable yet challenging.We report here a catalytic asymmetric peroxidation of anα,β-unsaturated triflone-kinetic resolution cascade reaction,which furnishes chiral peroxides in greater than 99.9%ee.The realization of this cascade reaction resulted from the development of two betaines as novel catalysts for chiral peroxide synthesis;one betaine promoted enantioselective peroxidation ofα,β-unsaturated triflones via conjugate addition affording peroxides in 80-92%ee,while the other betaine catalyzed kinetic resolution of the newly generated chiral peroxides to further increase the ee to greater than 99.9%.展开更多
The first example of benzylic C-H triflylation was accomplished with pyridine as a directing group. The reac- tion of various 2-benzylpyridines and （CF3SO2）20 in the presence of NEt3 in CH2Cl2 proceeded smoothly to ...The first example of benzylic C-H triflylation was accomplished with pyridine as a directing group. The reac- tion of various 2-benzylpyridines and （CF3SO2）20 in the presence of NEt3 in CH2Cl2 proceeded smoothly to afford the corresponding benzyl triflones in moderate to high yields.展开更多
基金We gratefully acknowledge funding from the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(grant no.2020R01004)the National Natural Science Foundation of China(grant no.U22A20389).
文摘An array of natural products bearing chiral peroxide motifs display antitumor,anticancer,and antiparasitic activities.However,there are very few catalytic asymmetric syntheses of chiral peroxides.Moreover,effective catalysts for asymmetric catalytic peroxidations are limited to chiral amines.To further expand synthetic access to chiral peroxides,the development of new catalysts realizing catalytic asymmetric peroxidation is highly desirable yet challenging.We report here a catalytic asymmetric peroxidation of anα,β-unsaturated triflone-kinetic resolution cascade reaction,which furnishes chiral peroxides in greater than 99.9%ee.The realization of this cascade reaction resulted from the development of two betaines as novel catalysts for chiral peroxide synthesis;one betaine promoted enantioselective peroxidation ofα,β-unsaturated triflones via conjugate addition affording peroxides in 80-92%ee,while the other betaine catalyzed kinetic resolution of the newly generated chiral peroxides to further increase the ee to greater than 99.9%.
基金We are grateful for the financial support from National Natural Science Foundation of China （Nos. 21502215, 21421002, 21332010, 21272036）, Strategic Priority Research Program of the Chinese Academy of Sciences （No. XDB20020000）, Youth Innovation Pro- motion Association CAS （No. 2016234）, and Shanghai Puj iang Program （No. 15PJ 1410300）.
文摘The first example of benzylic C-H triflylation was accomplished with pyridine as a directing group. The reac- tion of various 2-benzylpyridines and （CF3SO2）20 in the presence of NEt3 in CH2Cl2 proceeded smoothly to afford the corresponding benzyl triflones in moderate to high yields.
