We established a copper-catalyzed asymmetric alkynylation of the sp2 C–H bond of silylallenes, which was presented as an efficient method for the synthesis of enantioenriched skipped diynes with excellent enantioselectivity. The reaction was initiated by hydrogen atom abstraction of sp2 allenic C–H bonds, in which the resonance forms of allenic and propargylic radicals were chemo- and enantioselectively trapped by chiral alkynyl-Cu(II) species to deliver a variety of skipped diynes. The method features a broad substrate scope and robust functional group tolerance, accommodating both alkynyl silanes and boronic esters. This result is published in JACS. Congratulations Ping Zhao.

We disclosed a copper-catalyzed approach for the enantioselective allylic C(sp3)–H oxidation of terminal alkenes, facilitated by introducing a sterically bulky B2Im(C6F5)6 anion. Notably, a wide range of aryl-substituted terminal alkenes were used as limiting reagents, delivering various products with excellent enantioselectivity and regioselectivity (up to 99% ee, >20:1 b/l). Mechanistically, the bulky counteranion was found to be essential for achieving excellent enantioselective control and high catalytic efficiency. This result is published in JACS. Congratulations Yibo.