4'-Bromo-2-hydroxyacetophenone trifluoromethanesulfonate ester 4'-Bromophenacyl triflate 4'-Bromophenacyl trifluoromethanesulfonate 93128-04-2 BPTSE Methanesulfonic acid, trifluoro-, 2-(4-bromophenyl)-2-oxoethyl ester