New weakly coordinating chiral anions and their application in enantioselective catalysis Richard Collins and Mark Chadwick Imperial College London, UK Common organometallic catalysts are generally ionic, where the anionic-stabilisation can affect the reaction outcome. 1 The application of weakly coordinating chiral anions (WCCAs) in asymmetric counter-anion directed catalysis (ACDC) has the potential to improve current industrial procedures, reducing waste and increasing the sustainability of pharmaceutical reactions through enantioselective synthesis. We have synthesised a family of alkali metal (Na), alkali earth metal (Mg), and ammonium (Et 3 NH, s Bu 3 NH) and imidazolium salts of a new WCCA of the formula [B(C 6 F 5 )(C 6 Cl 5 ){3,5-(CF 3 ) 2 C 6 H 3 }{3,5-(Cl) 2 C 6 H 3 }] - . These have been benchmarked for their capabilities by comparing to known ACDC reactions as well as asymmetric hydrogenation reactions. 2 References
1. Riddleston, I. M. et al., Angew. Chem. Int. Ed. , 2018 , 57, 13982-140242- 2. R. J. Phipps, G. L. Hamilton, F. D. Toste, Nat. Chem. , 2012 , 4, 603-614
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