in tetrahydrofuran

(i) isooctane, (UV-irradiation), (ii) (heating); Multistep reaction;

tetrafluoroboric acid diethyl ether complex; trifluoroacetic acid; trifluoroacetic anhydride in dichloromethane T=-86°C;

TDBPA(1+)*SbCl6(1-); trifluoroacetic acid; trifluoroacetic anhydride in dichloromethane T=-78°C; other temperature; various reagents proportions; different concentrations; different amounts of initiator; Product distributionMechanism;

TDBPA(1+)*SbCl6(1-); trifluoroacetic acid; trifluoroacetic anhydride in dichloromethane T=-78°C; var. temp., ratios of reagents; var. Lewis acids; Product distributionMechanism;