School of Medicine and Tsinghua-Peking Joint Centers for Life Science, Tsinghua University, Beijing 100084 (China).
Angew Chem Int Ed Engl. 2015 Jun 1;54(23):6918-21. doi: 10.1002/anie.201502548. Epub 2015 Apr 23.
Reported herein is the rhodium-catalyzed enantioselective C-H bond silylation of the cyclopentadiene rings in Fe and Ru metallocenes. Thus, in the presence of (S)-TMS-Segphos, the reactions took place under very mild conditions to afford metallocene-fused siloles in good to excellent yields and with ee values of up to 97%. During this study it was observed that the steric hindrance of chiral ligands had a profound influence on the reactivity and enantioselectivity of the reaction, and might hold the key to accomplishing conventionally challenging asymmetric C-H silylations.
本文报道了铑催化的费托型和钌夹心型金属茂中环戊二烯环的对映选择性 C-H 硅烷化反应。在 (S)-TMS-Segphos 的存在下，该反应在非常温和的条件下进行，以良好至优秀的产率和高达 97%的对映选择性得到金属茂稠合硅烷。在这项研究中观察到，手性配体的空间位阻对反应的活性和对映选择性有深远的影响，这可能是实现传统挑战性不对称 C-H 硅烷化反应的关键。
