Synthesis of 1,4‐, 1,5‐, 2,6‐ and 2,7‐di‐t‐butylnaphthalene and of 1,4‐, 1,5‐, 2,6‐ and 1,8‐diisopropylnaphthalene

Abstract Mixtures of 2,6‐ and 2,7‐di‐t‐butylnaphthalene, obtained by the t‐butylation of naphthalene, can be conveniently separated making use of the fact that only the 2,6‐isomer gives an inclusion compound with thiourea. 1,4‐ and 1,5‐di‐t‐butylnaphthalene as well as 1,4‐ and 1,5‐diisopropylnaphthalene have been prepared starting from 1,4‐ and 1,5‐naphthalene‐dicarboxylic acid, respectively. The NMR spectra of these compounds reveal downfield shifts for the peri protons. 1,8‐Diisopropylnaphthalene was synthesized by an eight step synthesis starting from 1,8‐naphthalenedicarboxylic anhydride.