Reaction of p-substituted phenols 2 with a catalytic amount of 4-iodophenoxyacetic acid (1) and Oxone ® as a co-oxidant in tetrahydrofuran (THF) or 1,4-dioxane–water gave the corresponding p-quinols 3 in excellent yields. Reaction of p-dialkoxyarenes 4 in 2,2,2-trifluoroethanol–water gave the corresponding p-quinones 5 in excellent yield without purification. These reactions provide efficient and practical methods for the preparation of p-quinols and p-quinones from p-substituted phenols and p-dialkoxyarenes, respectively. This quinone synthesis was applied to synthesis of blattellaquinone (13), the sex pheromone of the German cockroach Blattella germanica.