Beilstein J. Org. Chem.2019,15, 1304–1312, doi:10.3762/bjoc.15.129
anion; trityliumsalt; Introduction
Carbocation Lewis acid catalysis has grown significantly over the last two decades [1][2][3][4][5][6][7][8][9][10][11][12][13]. The development of asymmetric carbocation catalysts has been long pursued but remains a challenging task. One strategy is to design and
; see Supporting Information File 1 for details).
We next tested the metal phosphate strategy in the Diels–Alder reaction of anthracene, for which a catalytic asymmetric version has not been achieved yet. Recently, we reported that the trityliumsalt [Ph3C][BArF], in situ generated by Ph3CBr and NaBArF
activity and up to 93% ee. Further studies are currently underway to elucidate the mechanistic details and to extend the chiral trityliumsalt catalysis to other reactions.
Dissociation of latent carbocation by the use of Lewis acids. a) UV–vis absorption spectra of TP (0.05 mM) upon the addition of Lewis