Secondary and tertiary amides were treated with trifluoromethanesulfonic (triflic) anhydride in the presence of pyridine at low temperatures to generate imino and iminium triflates. Successive treatment with 2,2-bishydroxymethyl-1- propanol in the pyridine buffered solution gave the corresponding 2,6,7-trioxabicyclo[2.2.2]octane orthoesters in good to excellent yields at below room temperature.