Abstract The title compound is synthesized starting from either 4-bromobenzyl tert- butyldimethylsilyyl ether (5b) or 4-bromobenzyl tert-butyl ether (5c) or–most simply–from 4- bromotoluene (5a). In the first step Br was replaced by Li using n-butyllithium, then the organometallic compounds were converted into the respective trifluoroacetophenones 6a–c with N-trifluoroacetylpiperidine. The azi moiety (diazirine) was prepared from the oximes ...