Regioselective C–F Bond Activation/C–C Bond Formation between Fluoropyridines and Cyclopropyl Groups at Zirconium
作者:Nuria Romero、Quentin Dufrois、Natalie Crespo、Anthony Pujol、Laure Vendier、Michel Etienne
DOI:10.1021/acs.organomet.0c00218
日期:2020.6.22
the problem of the strong and inert C–F bond activation of various fluoropyridines by zirconocene derivatives. Dicyclopropylzirconocene, [Cp2Zr(c-C3H5)2], thermally eliminates cyclopropane, giving the transient intermediate zirconabicyclobutane [Cp2Zr(η2-c-C3H4)] that cleaves a C–F bond of pentafluoropyridine selectively at position 2, forming new Zr–F and C–C bonds stereoselectively to give [Cp2Zr
本文探讨了锆茂衍生物对各种氟吡啶进行强而惰性的CF键活化的问题。Dicyclopropylzirconocene,混合[Cp 2 Zr的(ç -C 3 ħ 5)2 ],热消除环丙烷,给瞬时中间体zirconabicyclobutane的[Cp 2 Zr的(η 2 - ç -C 3 ħ 4)]裂解的C-F键在位置2选择性五氟,形成新ZRF和C-C键立体选择性,得到的[Cp 2 ZRF ç -顺式- CHCH 2 CH(2-NC 5 ˚F4 }}]。DFT计算表明,选择性的结果是氮杂碳环中间体的初始形成,该中间体经历开环和CF键断裂。转移金属化与各种环丙基供体产量的[Cp 2 Zr的(ç -C 3 ħ 5) Ç -顺式- CHCH 2 CH(2-NC 5 ˚F 4)}]具有取决于供体的性质的选择性。合成周期被实现时的[Cp 2 Zr的(ç -C 3 ħ 5) Ç -顺式- CHCH 2