Chiral phosphoric acids are incorporated into indium-based metal-organicframeworks (In-MOFs) by sterically preventing them from coordination. This concept leads to the synthesis of three chiral porous 3D In-MOFs with different network topologies constructed from three enantiopure 1,1'-biphenol-phosphoric acid derived tetracarboxylate linkers. More importantly, all the uncoordinated phosphoric acid
Highly Stable Zr(IV)-Based Metal–Organic Frameworks with Chiral Phosphoric Acids for Catalytic Asymmetric Tandem Reactions
作者:Wei Gong、Xu Chen、Hong Jiang、Dandan Chu、Yong Cui、Yan Liu
DOI:10.1021/jacs.9b02294
日期:2019.5.8
Heterogeneous Brønsted acid catalysts featuring high porosity, crystallinity, and stability have been of great interest for both fundamental studies and practical applications, but synthetically, they still face a formidable challenge. Here, we illustrated a ligand design strategy for directly installing chiral phosphoric acid catalysts into highly stable Zr-MOFs by sterically protecting them from coordinating
2-aminobenzamide and aldehydes, catalyzed by a novel chiral organocatalyst, was realized. The organocatalyst was found to be very effective and highly enantioselective for such cascade reactions at room temperature, affording 2,3-dihydroquinazolinones in excellent yields (up to 99%) with enantiomericexcesses of up to 97%. The best level of stereocontrol was obtained for aromatic/aliphatic aldehydes with ortho
Highly enantioselective synthesis of dihydroquinazolinones through Sc(OTf)3-catalyzed intramolecular amidation of imines
作者:Tao Deng、Hongjun Wang、Chun Cai
DOI:10.1016/j.jfluchem.2014.11.008
日期:2015.1
A Sc(OTf)(3)-catalyzed intramolecular amidation of imines with a novel fluorous bis(oxazolines) as ligand is presented. The corresponding chiral dihydroquinazolinones were obtained in 76-94% yield with enantioselectivities up to 98%. The fluorous ligand can be easily recovered and reused at least three times without significant loss of enantioselectivity. (C) 2014 Elsevier B.V. All rights reserved.
Highly Enantioselective Synthesis of Dihydroquinazolinones Catalyzed by SPINOL-Phosphoric Acids
作者:Dan Huang、Xuejian Li、Fangxi Xu、Luhang Li、Xufeng Lin
DOI:10.1021/cs400591u
日期:2013.10.4
The asymmetric condensation/amine addition cascade sequence of 2-aminobenzamides and aldehydes catalyzed by chiral spirocyclic SPINOL-phosphoric acids was realized. SPINOL-phosphoric acid 1j was found to be a general, highly enantioselective organocatalyst for such cascade reactions at room temperature, affording 2,3-dihydroquinazolinones in excellent yields (up to 99%) with good to excellent ee's (up to 98%). The best level of stereocontrol was obtained for aromatic aldehydes with an ortho substituent.