Synergistic Activation Strategy to Achieve Rh₂(II)-Catalyzed Asymmetric Cycloisomerization of 1,n-Enynes

Dirhodium: carbene transformations and beyond

“…With the enynal 15 as the substrate, they introduced a synergetic effect to achieve the activation of enyne, that is, the electron-withdrawing activation and the C–H ⋯ O interaction (Scheme 5). 27 In this way, the substrate 15 could be catalyzed successfully to give 16 selectively by both the achiral dirhodium Rh 2 (OPiv) 4 and the chiral one Rh 2 ( S -BTPCP) 4 . Of particular note was that the reaction could be conducted at 0.1 mol% catalyst loading under mild conditions.…”

Rh2(ii)-catalyzed enantioselective intramolecular Büchner reaction and aromatic substitution of donor–donor carbenes

“… 15 In our previous work, we realized the asymmetric intramolecular C–H insertion and cyclopropanation with enynones as carbene precursors. 16 With our continuous interest in the development of donor type metal-carbenes, 17 herein we would like to report the first example of the chiral Rh 2 ( ii )-catalyzed enantioselective Büchner reaction with donor–donor carbenes ( Scheme 1C , right). In addition, the asymmetric aromatic substitution is also achieved using the same catalyst as well ( Scheme 1C , left).…”