Di [3-(4'-methoxyphenyl)-2,2,4,4-tetramethylpentan-3-yl] oxalate (4a) and the analogous bis tetrahydropyranyl ether (4b) have been synthesized, and X-ray crystallography of the former shows an almost symmetrically staggered relationship of the t-butyl groups with respect to the plane of the benzene ring.