NMR enantiodifferentiation of thiiranium cations by chiral hexacoordinated phosphate anions

BINPHAT anion—rather than TRISPHAT—is an efficient NMR chiral shift reagent for thiiranium ions such as c-2,t-3-di-tert-butyl-r-1-methylthiiranium and t-2-tert-butyl-c-3-phenyl-r-1-methylthiiranium cations. This is the first report on the NMR enantiodifferentiation of such chiral cations.