Chiral Phosphabarrelene Ligands: Synthesis and Evaluation in Rhodium-Catalyzed Asymmetric Hydrogenation

Abstract

The first chiral and enantiomerically pure monodentate and bidentate phosphabarrelene ligands have been prepared and their potential in rhodium-catalyzed asymmetric hydrogenation has been evaluated.

Key words

asymmetric catalysis - hydrogenation - ligands - phosphorus - rhodium

References

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8

³¹P NMR data of [Rh(cod)(6a)]BF₄ (121.468 MHz, CDCl₃): P_phosphite: δ = 125.2 (dd, ¹ J _P,Rh = 254.8 Hz, ² J _P,P = 52.4 Hz; P_barrelene: δ = -14.2 (dd, ¹ J _P,Rh = 154.8 Hz, ² J _P,P = 52.4 Hz).