P-Chiral Monodentate Diamidophosphites − New and Efficient Ligands for Palladium-Catalysed Asymmetric Allylic Substitution

Novel P*‐monodentate diamidophosphite ligands have been prepared by a one‐step phosphorylation of alcohols or amines. Both the electronic and the steric demands of the ligands have been estimated quantitatively. Neutral [Pd(allyl)Cl(L)] and cationic [Pd(allyl)(L)2]+ BF4− complexes have been obtained by starting from [Pd(allyl)Cl]2. The new ligands have demonstrated high enantioselectivity in the Pd‐catalysed allylic substitution reactions of 1,3‐diphenylallyl acetate with NaSO2pTol (up to 97% ee), PhCH2NH2 (up to 95% ee) and CH2(CO2Me)2 (up to 97% ee). Application of the P*‐monodentate diamidophosphites to the asymmetric catalytic synthesis of chiral carborane derivatives has also been demonstrated. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)