The dimerization reactions of 2-bromo-3,5,6-trimethyl-1,4-benzoquinone have been examined. 2,2'-Dimeric benzoquinone was prepared via a Stile-type homocoupling, whereas an oxepin was formed by the treatment of the title quinone with hexamethylditin, CuI, and (+/-)-BINAP in DMF. Two dimerization reactions involving a hetero Diels-Alder reaction between quinones and quinone methides were also observed.