A Highly Reactive and Catalytically Active Model System for Intradiol‐Cleaving Catechol Dioxygenases: Structure and Reactivity of Iron( III ) Catecholate Complexes of N,N′‐Dimethyl‐2,11‐diaza[3.3](2,6)pyridinophane

The reactivity of intradiol-cleaving catechol dioxygenases can be modeled with the complex cation 1. The complex reacts nearly quantitatively with molecular oxygen yielding 3,5-di-tert-butylmuconic anhydride (3) and 3,5-di-tert-butyl-5-carboxymethyl-2-furanone in a 1:1 ratio. The catalytic oxygenation reaction of 2 [Eq. (a)] gives 3 in 70% yield and with a turnover number of 54. dbcH2 = 3,5-di-tert-butylcatechol; L-N4Me2 = N,N′-dimethyl-2,11-diaza[3.3](2,6)pyridinophane.