Liu Haidong, Tian Lifang, Wang Hui, Li Zhi-Qiang, Zhang Chi, Xue Fei, Feng Chao
Technical Institute of Fluorochemistry (TIF), Institute of Advanced Synthesis (IAS), School of Chemistry and Molecular Engineering, Nanjing Tech University Nanjing 211816 P. R. China
Institute of Material Physics & Chemistry, College of Science, Nanjing Forestry University Nanjing 210037 China.
Chem Sci. 2022 Feb 15;13(9):2686-2691. doi: 10.1039/d2sc00302c. eCollection 2022 Mar 2.
-Difluorocyclopropane diester is disclosed as a new type of donor-acceptor cyclopropane, which smoothly participates in (3 + 2)-cycloadditions with various aldehydes and ketones. This work represents the first application of -difluorine substituents as an unconventional donor group for activating cyclopropane substrates in catalytic cycloaddition reactions. With this method, a wide variety of densely functionalized -difluorotetrahydrofuran skeletons, which are otherwise difficult to prepare, could be readily assembled in high yields under mild reaction conditions. Computational studies show that the cleavage of the C-C bond between the difluorine and diester moieties occurs upon a S2-type attack of the carbonyl oxygen.
二氟环丙烷二酯作为一种新型的给体-受体环丙烷被公开，它能顺利地与各种醛和酮发生(3 + 2)环加成反应。这项工作代表了首次将二氟取代基作为一种非常规的给体基团，用于在催化环加成反应中活化环丙烷底物。通过这种方法，在温和的反应条件下，可以很容易地以高产率组装出各种难以制备的高度官能化的二氟四氢呋喃骨架。计算研究表明，在羰基氧的S2型进攻下，二氟和二酯部分之间的C-C键会发生断裂。
