A Convenient Synthesis of Carboxanilides from Silyl Carboxylates and Weakly Nucleophilic Anilines Using<i>p</i>-Trifluoromethylbenzoic Anhydride and a Catalytic Amount of Active Titanium(IV) Salt
Various carboxanilides are prepared in excellent yields from nearly equimolar amounts of silyl carboxylates and the corresponding weakly nucleophilic anilines under mild conditions by using p-trifluoromethylbenzoic anhydride and a catalytic amount of active titanium(IV) salt.
In the presence of a catalytic amount of active titanium(IV) salt generated in situ from 1 mol of TiCl4 and 2 mol of AgOTf, weakly nucleophilic anilines react under mild conditions with nearly equimolar amounts of silyl carboxylates to afford the corresponding anilides in excellent yields using 4-(trifluoromethyl)benzoic anhydride. The mixed anhydride formed in situ from trimethylsily acetate and 4-(trifluoxomethyl)benzoic anhydride, a key intermediate of this reaction, was detected by 1H NMR experiment. Further, it was shown that the reaction of the mixed anhydrides and 2-nitroaniline was faster than that of the corresponding homo anhydrides and 2-nitroaniline.
Silver-catalyzed nitrosation and nitration of aromatic amides using NOBF<sub>4</sub>
作者:Sa Li、Wentao Liu、Xiao-Feng Xia
DOI:10.1039/d3ob01729j
日期:——
Divergent aromatic ring nitrosation and nitration of aromatic amides are reported using NOBF4 as the electrophile under silver-catalyzed conditions. The reactions proceed efficiently with a wide range of compatible functionalities providing ortho-position nitrosation products, deacylation nitrosation products, and nitration products from different tertiary and secondary aromatic amides.