Title: MetalOrganic Network Materials for Asymmetric Catalysis
1Metal-Organic Network Materials forAsymmetric
Catalysis
Joseph M. Tanski, Department of Chemistry, Vassar
College, Poughkeepsie, NY 12604, USA
- Matched pair asymmetric activation phenomena are
a powerful approach to enhance enantioselectivity
in existing catalytic systems. We have discovered
that resolved titanium sec-butoxide, combined
with resolved BINOL (BINOL 1,1'-bi-2-naphthol)
of the opposite configuration
designation, yields a dichiral matched pair that
mediates the addition of dimethyl zinc to
benzaldehyde with higher enantioselectivity than
resolved BINOL with achiral Ti(OiPr)4 (40 ee) or
the mismatched dichiral pair (40 ee).
Metal-Organic Network Materials prepared from
titanium alkoxides and bis(hydroxyaryl)
functionalized organic spacer ligands have been
structurally characterized by X-ray
crystallography, revealing that solvent donor
ability influences the dimensionality of the
materials obtained.
We are working on incorporating a chiral
bidentate ligand inside of a porous network such
that, when combined with resolved titanium
sec-butoxide, the material will serve as an
insoluble, recyclable, heterogeneous version of
our dichiral catalyst.