Chiral porous organic frameworks for asymmetric heterogeneous catalysis and gas chromatographic separation
作者:Jinqiao Dong、Yan Liu、Yong Cui
DOI:10.1039/c4cc07648f
日期:——
Three chiral robust diene-based porous organic frameworks (POFs) are prepared. POF-1 is shown to be an efficient heterogeneous catalyst after metallation for asymmetric conjugation addition with up to 93% ee, and it can also function as a new chiral stationary phase for gas chromatographic separation of racemates.
it both ways: A novel class of chiral sulfoxide‐olefin ligands was synthesized from a single chiral source. These ligands were evaluated in rhodium‐catalyzed 1,4‐additions of arylboronic acids to electron‐deficient olefins, and remarkable olefin‐directed reversal of stereoselectivity (up to >99 % ee, R isomer; 98 % ee, S isomer) was observed when the reversal ligand pair L1 (branched olefin) and L2
Fine‐Tuning the Bicyclo[3.3.1]nona‐2,6‐diene Ligands: Second Generation 4,8‐Substituted Dienes for Rh‐Catalyzed Asymmetric 1,4‐Addition Reactions
作者:Vidmantas Bieliūnas、Sigitas Stončius
DOI:10.1002/cctc.202100638
日期:2021.9.7
C2-symmetric 4,8-endo,endo-bis(alkoxy) bicyclo[3.3.1]nona-2,6-diene ligands possessing additional 4,8-exo,exo substituents is reported. The 4,8-exo,exo groups provide a further element for fine-tuning of the ligand structure by enforcing conformational rigidity of the 4,8-endo,endo side chains. Such tetrasubstituted bicyclo[3.3.1]nona-2,6-dienes were employed as steering ligands in the rhodium-catalyzed arylation
Highly Practical Catalytic Asymmetric 1,4-Addition of Arylboronic Acids in Water Using New Hydrophilic Chiral Bicyclo[3.3.0] Diene Ligands
作者:Chen-Guo Feng、Zhi-Qian Wang、Cheng Shao、Ming-Hua Xu、Guo-Qiang Lin
DOI:10.1021/ol801665z
日期:2008.9.18
The first Rh-diene-catalyzed aqueous asymmetric1,4-addition of alpha,beta-unsaturated carbonyl compounds with arylboronic acids has been realized. By using a hydrophilic bicyclo[3.3.0] dieneligand, the reactions can be performed successfully in neat water at room temperature to afford the corresponding products in good yields and with very high enantioselectivities for both cyclic and linear substrates
作者:Holger Grugel、Fabian Albrecht、Tobias Minuth、Mike M. K. Boysen
DOI:10.1021/ol3015896
日期:2012.7.20
pseudo-enantiomeric olefinligands were designed from d-glucose and d-galactose. These ligands yield consistently excellent levels of enantioselectivity in Rh(I)-catalyzed 1,4-additions of aryl- and alkenylboronic acids to achiral enones and high diastereoselectivity with chiral substrates. Contrary to established olefinligands, they are obtained enantiomericallypure via short syntheses without racemic