A homochiral porous metal-organic framework for highly enantioselective heterogeneous asymmetric catalysis.
A homochiral porous noninterpenetrating metal-organic framework (MOF), 1, was constructed by linking infinite 1D [Cd(mu-Cl)2]n zigzag chains with axially chiral bipyridine bridging ligands containing orthogonal secondary functional groups. The secondary chiral dihydroxy groups accessible via the large open channels in 1 were utilized to generate a heterogeneous asymmetric catalyst for the addition of diethyzinc to aromatic aldehydes to afford chiral secondary alcohols at up to 93% enantiomeric excess (ee). Control experiments with dendritic aromatic aldehydes of different sizes indicate that the heterogeneous asymmetric catalyst derived from 1 is both highly active and enantioselective as a result of the creation of readily accessible, uniform active catalyst sites inside the porous MOF.
Wu
Chuan-De
CD
Department of Chemistry, CB#3290, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
Hu
Aiguo
A
Zhang
Lin
L
Lin
Wenbin
W
D000447:Aldehydes / Q000138:chemical synthesis / Q000737:chemistry; D002384:Catalysis; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D016062:Porosity; D013237:Stereoisomerism; D014025:Titanium / Q000737:chemistry*
D000447:Aldehydes; D008024:Ligands; D009942:Organometallic Compounds; D014025:Titanium