2,6-Dimethylbenzoquinone

2,6-Dimethylbenzoquinone (2,6-DMBQ) is a benzoquinone derivative. 2,6-Dimethylbenzoquinone promotes Photosystem II-mediated photoelectrochemical water oxidation via electron transfer between spinach chloroplast Photosystem II membranes and carbon paste electrodes, and accepts electrons from Photosystem II during oxygen evolution assays. 2,6-Dimethylbenzoquinone undergoes direct photolysis in aqueous solution under 365 nm conditions, producing 2,6-dimethylhydroquinone and 3-hydroxy-2,6-dimethylbenzoquinone^[1][2]. In Vitro:2,6-Dimethylbenzoquinone (0.75-1% (w/w); within 10 h) functions as an electron-transfer mediator between spinach chloroplast PS-II-enriched membranes and a carbon paste electrode, generating an anodic steady-state photocurrent under illumination that follows Michaelis-Menten kinetics with a K'_DMQ of 0.97 mM and a maximum limiting current of 13.4 μA^[1].
2,6-dimethylbenzoquinone (19 μM; up to 30 min irradiated at 365 nm) undergoes direct photodegradation with a quantum yield of 0.47, producing DMHQ and OHDMBQ, while slow dark reaction yields only trace DMHQ, with no significant pH dependence in the range 2.90-6.00^[2].