d-Mannitol-derived novel chiral thioureas: Synthesis and application in asymmetric Henry reactions
作者:Miaoxi Liu、Nan Ji、Li Wang、Peng Liu、Wei He
DOI:10.1016/j.tetlet.2018.01.082
日期:2018.3
Five novel thioureas have been obtained through multi-step reactions from d-Mannitol as starting material and applied as catalysts in the asymmetric Henry reaction. Using catalyst 7a, (1S,2R)-2-nitro-1-phenylpropan-1-ol containing two chiral centers was obtained in high yield and with high selectivity (up to 95% yield, 87% ee, 91:9 dr). This catalyst also retained activity in the presence of water
The steric and electronic properties of chiral Schiff base ligands derived from cinchona alkaloids were evaluated in asymmetric Henry reactions. Amongst these, the stericallyhindered ligand 2 showed outstanding catalytic efficiency in the Cu(II) catalyzed asymmetric addition of nitroalkanes to a variety of aldehydes to afford the desired adducts in high yields (up to 97%) with excellent enantioselectivities
Synthesis and structural characterization of a novel dinuclear Cu(<scp>ii</scp>) complex: an efficient and recyclable bifunctional heterogeneous catalyst for the diastereoselective Henry reaction
作者:Datta Markad、Sanjay K. Mandal
DOI:10.1039/c8dt00708j
日期:——
describe the synthesis and structural characterization of a novel dinuclear Cu(II) complex containing a new flexible mixed pyridine-carboxylate ligand. Single crystal X-ray diffraction reveals its uniqueness with two coordinated water molecules and four uncoordinated pyridyl groups. Utilizing the bifunctional catalytic sites, it has been found to be an efficient, robust and recyclableheterogeneous catalyst
Binaphthyl-Proline Hybrid Chiral Ligands: Modular Design, Synthesis, and Enantioswitching in Cu(II)-Catalyzed Enantioselective Henry Reactions
作者:Chao Yao、Yaoqi Chen、Chao Wang、Ruize Sun、Haotian Chang、Ruiheng Jiang、Lin Li、Xin Wang、Yue-Ming Li
DOI:10.1021/acs.joc.2c01127
日期:——
Chiral O–N–N tridentate ligands were designed from proline and BINOL. Their design strategy and performance were evaluated using a copper(II)-catalyzed asymmetric Henryreaction as a model. The desired β-nitroalcohols were obtained in up to 94% ee’s. Preliminary results suggested that the stereofacial selection of the reactions was mainly controlled by the chiral diamine moiety derived from proline