| Abstract
| - Alkynyl-functionalized amino alcohols have been covalently supported on azidomethylpolystyrene resinswith different levels of functionalization through Cu(I)-catalyzed 1,3-dipolar cycloadditions (“clickchemistry”). The resulting 1,2,3-triazole-substituted resins, characterized by different levels of ligandloading and, depending on the nature of the alkynyl-functionalized amino alcohol, the presence of aone-carbon, four-carbon, or eight-carbon linear spacer, have been tested as catalysts in the enantioselectivephenyl transfer from zinc to aldehydes. High catalytic activities and enantioselectivities (up to 82% ee)have been recorded. The influence of structural characteristics of the resin on enantioselectivity arediscussed, and the limitations in enantiocontrol inherent to the use of a 1,2,3-triazole linker have beenrationalized with the help of DFT calculations on model systems.
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