The Copper-catalyzed Direct Hydroxylation Of Benzamides Assisted By An N,O Bidentate Directing Group

In this thesis, a series of benzamides1bearing2-aminopyridine1-oxidemoieties were synthesized and characterized. Then Cu(II)-catalyzed hydroxylation ofbenzamides was achieved by using2-aminopyridine1-oxide as an N,O-bidentedirecting group. The main research contents were as follows:1. Synthesis of2-benzamidopyridine1-oxide derivatives1All benzamides1bearing2-aminopyridine1-oxide moiety were synthesizedfrom the corresponding benzoic acids and2-Aminopyridine1-oxide using EDCI asdehydrant, DMAP as catalyst, CH2Cl2as solvent. All new compounds1a-r werecharacterized by1H NMR,13C NMR and HRMS.(Scheme1).2. Cu(II)-catalyzed hydroxylation of benzamides1First of all, the2-benzamidopyridine1-oxide1a was choosen as modelsubstrate to screen the optimum reaction condition. Under optimal condition, theproduct could be obtained with up to82%yield, and the subtrate containing naphthyl,bromo and iodo can also afford the corresponding compounds.(Scheme2)...