The contra-thermodynamic isomerization of α- and β-substituted cinnamate derivatives catalyzed by the Cu(OAc)2/rac-BINAP complex under blue light irradiation is reported. The use of an oxazolidinone template, which favored the complexation of the copper catalyst to the substrate, allowed the E → Z isomerization of the catalytically formed chromophore under simple and robust reaction conditions in good
Enantioselective Synthesis of Optically Active Alkanephos- phonates<i>via</i>Rhodium-Catalyzed Asymmetric Hydrogenation of β-Substituted α,β-Unsaturated Phosphonates with Ferrocene-Based Monophosphoramidite Ligands
series of chiral β-substituted alkanephosphonates was synthesized in high enantioselectivities via the first rhodium-catalyzedasymmetrichydrogenation of the corresponding β-substituted-α,β-unsaturated phosphonates using a ferrocene-derived monophosphoramidite ligand, with which up to 99.5% ee have been achieved for the hydrogenation of (E)-substrates and 98.0% ee for (Z)-substrates.
Heteroleptic Copper-Based Complexes for Energy-Transfer Processes: <i>E</i> → <i>Z</i> Isomerization and Tandem Photocatalytic Sequences
作者:Corentin Cruché、William Neiderer、Shawn K. Collins
DOI:10.1021/acscatal.1c01983
日期:2021.7.16
Energy-transfer processes involving copper complexes are rare. Using an optimized heteroleptic copper complex, Cu(bphen)(XantPhos)BF4, photosensitized E → Z isomerization of olefins is demonstrated. The XantPhos ligand afforded sensitizers with improved catalyst stability, while the bphen ligand lengthened the excited-state lifetime. A series of 25 di- and trisubstituted alkenes underwent photoisomerization