Synthesis and Properties of Substituted 1,6-Dioxapyrene Donors

The synthesis of substituted 1,6-dioxapyrenes, 2b-g, from 2,6-dipropyl-l,5-naphthalenediol (7a) or 2,6-dimethyl-1,5-naphthalenediol (7b) is described. Diol 7a was prepared by Claisen allylic rearrangement followed by reduction, and 7b was prepared by Mannich reaction of 1,5-naphthalenediol followed by base-promoted hydrogenolysis. The 1,6-dioxapyrenes can be oxidized to stable cation radicals at +0.2-0.35 V vs SCE and to dications at +0.8-1.20 V. The preparation of some tetracyanoquinodimethane salts and binary cation radical salts of the 1,6-dioxapyrenes is reported.