New soluble TADDOL-bearing polymers. Preparation and their use as Ti-complex catalysts for enantioselective addition of diethylzinc to benzaldehyde

Chiral catalysts immobilized on achiral polymers: effect of the polymer support on the performance of the catalyst

“…129,130 The high potential of TADDOL ligands (a,a,a 0 ,a 0 -tetraaryl-1,3-dioxolane-4,5-dimethanol) as chiral auxiliaries in catalysis and separation processes 131 has led different groups to study their immobilization on a variety of supports. [132][133][134][135][136][137][138][139] In the case of supported Ti-TADDOLates 62 (Fig. 10) prepared by grafting and studied for the Diels-Alder cycloaddition of cyclopentadiene and 3-crotonoyl-1,3-oxazolidin-2-one using a 10 : 1 catalyst dienophile ratio, 129,130 no clear rationale was given to explain the observed increase in activity, but the presence of changes in the mechanism can be envisaged, in particular taking into account the potential participation in this reaction of several complexes with different molecularities.…”

Triple Thermoresponsiveness of a TADDOL-Based Homopolymer through the Formation of Supramolecular Complexes with Chiral Guest Molecules at Variable Ratios

“…In the presence of the suitable guests for the TADDOL, they are expected to have thermoresponsiveness in less-polar solvents, and the control of the solubility by the chiral recognition is also expected. Nevertheless, although polymers containing TADDOL were reported as catalysts or for chiral recognition, , no examples have ever been reported about stimulus-responsive polymers. Herein, we report the new thermoresponsive polymer tethering the TADDOL group in the polymer chain induced by chiral guests.…”

Using Soluble Polymer Supports To Facilitate Homogeneous Catalysis

“…80 The product, NCPS-bound TAD-DOL (43) was then used to catalyze the enantioselective addition of Et 2 Zn to benzaldehyde as shown in eq 48.…”