N. Hirai, Y. Tatsukawa, M. Kameda
Jul 12, 2006
Citations
0
Influential Citations
20
Citations
Journal
Tetrahedron
Abstract
Abstract The oxidation of trimethylbenzenes was examined with air or O 2 using N , N ′, N ″-trihydroxyisocyanuric acid (THICA) as a key catalyst. Thus, 1,2,3-, 1,2,4-, and 1,3,5-trimethylbenzenes under air (20 atm) in the presence of THICA (5 mol %), Co(OAc) 2 (0.5 mol %), Mn(OAc) 2 , and ZrO(OAc) 2 at 150 °C were oxidized to the corresponding benzenetricarboxylic acids in good yields (81–97%). In the aerobic oxidation of 1,2,4-trimethylbenzene by the THICA/Co(II)/Mn(II) system, remarkable acceleration was observed by adding a very small amount of ZrO(OAc) 2 to the reaction system to form 1,2,4-benzenetricarboxylic acid in excellent yield (97%). In contrast, no considerable addition effect was observed in the oxidation of 1,3,5-trimethylbenzene. This aerobic oxidation by the present catalytic system provides an economical and environmentally benign direct method to benzenetricarboxylic acids, which are very important polymer materials.