The synthesis of new enantiopure wide-bite-angle diphosphanes is described as well as their use in the palladium-catalyzed asymmetric fluorination of α-cyanoacetates. Enantiomeric excesses up to 93 % were obtained when Pd(OAc)2-SPANphos was used as catalyst for the fluorination of ethyl 2-cyano-2-phenylacetate with N-fluorobenzenesulfonimide (NFSI).
SPANphos ligands in palladium-catalyzed asymmetric fluorination
Eur. J. Org. Chem. 2012, 4844-4852.