Oxygenation of 2,6-di-t-butylphenol catalysed by a new cobalt(II) complex [Co(babp)]: a salen analogue having higher catalytic activity, selectivity, and durability

Abstract

The deprontated form of the cobalt(II) complex of 6,6′-bis(benzoylamino)-2,2′-bipyridine [Co(babp)] shows excellent catalytic activity in the selective oxygenation of 2,6-di-t-butylphenol (DTBP) to 2,6-di-t-butyl-p-benzoquinone (DTBQ) in the presence of an appropriate base. The durability of [Co(babp)] as an oxygenation catalyst is much higher than that of [Co(salen)] and, furthermore, the reduced catalytic activity of the complex after repeated use can easily be improved to a certain extent by heating at 200 °C under reduced pressure.