Manganese(III) acetate is found to be an efficient catalyst to perform oxidation of 3,5-di-tert-butylcatechol (DTBC) to 3,5-di-tert-butylbenzoquinone (DTBQ) and 2-aminophenol (OAP) to 2-aminophenoxazinone (APX). The kcat values are 1.72(2) x 10(3) and 2.8(2) x 10(2) h(-1) for the formation of DTBQ and APX, respectively. The turnover number of APX formation is highest among the synthetic mimics. ESI-MS studies of DTBC oxidation suggest formation of a MnIV intermediate. Manganese(III) acetate is also capable of oxidative CC bond coupling in sterically hindered phenols to form biaryls in 65-94% yield. (C) 2014 Elsevier B.V. All rights reserved.