Regio‐ and Stereoselective Synthesis of Tetrasubstituted Alkenes via Ruthenium(II)‐Catalyzed C–H Alkenylation/Directing Group Migration

Abstract

Herein we report the regio-and stereoselective synthesis of tetrasubstituted alkenes from N-carbamoyl indoles and alkynes via ruthenium(II)-catalyzed CÀ H alkenylation/directing group migration, in which the carbamoyl directing group is endowed with a dual role of auxiliary group and migrating acylation reagent via CÀ N bond cleavage. This method features broad substrate scope, high atom-and step-economy, good functional group tolerance and mild redox-neutral conditions at room temperature. A series of structurally diverse tetrasubstituted alkenes were synthesized in good to excellent yields, highlighting the efficiency of this method.

Enhanced Photoelectrocatalytic Activity of CuO/CuNb2O6 Heterojunction Photocathodes for Efficient Solar Water Splitting

“…The incident photon‐current conversion efficiency (IPCE) of CuO, CNO, and CuO/CNO was measured at 0.4 V vs. RHE to determine the wavelength‐dependent quantum efficiency for the photocathode, as shown in Figure 7b. The CuO/CNO heterojunction had a significantly higher photocurrent conversion efficiency throughout wavelength range than for the CuO and CNO thin films, indicating improved photocurrent performance [63–65] . The initial wavelength for the IPCE measurements of the CuO/CNO heterojunction was established at 840 nm, followed by a gradual increase observed towards shorter wavelengths.…”

Redox-neutral rhodium(iii)-catalyzed divergent synthesis of tetrasubstituted 1,3-enynes and alkynylated benzofurans

“…Nevertheless, the synthetic community has made their pioneering efforts in developing C–H functionalization/DG migration cascades. 4 In particular, the C–H alkenylation/DG migration with alkynes via Co( iii ), 5 Ru( ii ), 6 Rh( iii ) 7 and Ir( iii ) 8 catalysis has been well studied for the synthesis of tetrasubstituted alkenes (Scheme 1b). By contrast, the C–H alkenylation/DG migration with 1,3-diynes, which carry two adjacent carbon–carbon triple bonds, has been seldom explored (Scheme 1c).…”