Impact of Catalyst Deuteration on the Reactivity of Chiral Phase‐Transfer Organocatalysts

Abstract

AbstractSite‐specifically deuterated organocatalysts were prepared and found to show improved reactivity over the non‐deuterated analogs. Two privileged C2‐symmetric chiral binaphthyl‐modified tetraalkylammonium salts were selected for this study. The stability of these phase‐transfer catalysts was generally improved by site‐specific deuteration, though the degree of improvement was structure dependent. In particular, a large secondary kinetic isotope effect was observed for the tetradeuterated phase‐transfer catalyst. The performance of these deuterated catalysts in the asymmetric catalytic alkylation of amino acid derivatives was better than that of non‐deuterated analogs at low catalyst loadings. The results suggest that catalyst deuteration is a promising strategy for enhancing the stability and performance of organocatalysts.