Fluoronium Organocatalysis

Significance

The authors report the N-fluoropyridinium triflate (1) catalyzed, diastereoselective synthesis of N-aryl aziridines. The catalyst, representing a powerful source of the fluoronium cation (F⁺), provides the resulting aziridines in good yields and with occasionally outstanding cis selectivity. Furthermore, the catalyst proved to be compatible with functional groups like acetals or silanes. The latter case was demonstrated in a shortened synthesis of rac-chloramphenicol, a powerful antibiotic substance, obtained through an N-silylated aziridine which liberated its deprotected NH equivalent during workup.