756530-16-2Relevant academic research and scientific papers
Copper(I)-Catalyzed Enantioconvergent Borylation of Racemic Benzyl Chlorides Enabled by Quadrant-by-Quadrant Structure Modification of Chiral Bisphosphine Ligands
Iwamoto, Hiroaki,Endo, Kohei,Ozawa, Yu,Watanabe, Yuta,Kubota, Koji,Imamoto, Tsuneo,Ito, Hajime
supporting information, p. 11112 - 11117 (2019/07/17)
The first copper(I)-catalyzed enantioselective borylation of racemic benzyl chlorides has been realized by a quadrant-by-quadrant structure modulation of QuinoxP*-type bisphosphine ligands. This reaction converts racemic mixtures of secondary benzyl chlorides into the corresponding chiral benzylboronates with high enantioselectivity (up to 92 % ee). The results of mechanistic studies suggest the formation of a benzylic radical intermediate. The results of DFT calculations indicate that the optimal bisphosphine-copper(I) catalyst engages in noncovalent interactions that efficiently recognize the radical intermediate, and leads to high levels of enantioselectivity.
Asymmetric transfer hydrogenation of 1-naphthyl ketones by an ansa-Ru(II) complex of a DPEN-SO2N(Me)-(CH2)2(η 6-p-tol) combined ligand
Kisic, Andrea,Stephan, Michel,Mohar, Barbara
, p. 1614 - 1617 (2013/06/26)
The first second-generation designer Ru(II) catalyst 1b featuring an enantiopure N,C-(N-ethylene-N-methyl-sulfamoyl)-tethered (DPEN- κ2N,N′)/η6-toluene hybrid ligand is introduced. Using an S/C = 1000 in HCO2H-Et3N 5:2 transfer hydrogenation medium, secondary 1-naphthyl alcohols are obtained in up to >99.9% ee under mild conditions. Mechanistic factors are discussed.
