N,O-Bis(trifluoroacetyl)hydroxylamine as a useful electrophilic nitrogen source: catalytic synthesis of N-(trifluoroacetyl)sulfilimines

[formula: see text] In the presence of catalytic quantites of Cu(OTf)2 the novel hydroxamic acid anhydride salt functions competently in the trifluoroacetamidation of sulfides to afford N-(trifluoroacetyl)sulfilimines. The salient features of this salt include its ease of synthesis from the inexpensive, commercially available starting materials trifluoroacetic anhydride and hydroxylamine hydrochloride.