Eine ungewöhnliche Chlorwasserstoff-Abspaltung: syn-Eliminierung aus einem sterisch behinderten,aber freidrehbaren Halogenkohlenwasserstoff

An Unusual Dehydrochlorination: syn-Elimination from a Sterically Hindered, but Free Rotating Halogenated Hydrocarbon Depending on the solvent, the meso-3, 4-dichloro-2,2,5,5-tetramethylhexane undergoes base-promoted dehydrochlorination in a syn- or anti-periplanar manner, thus affording (Z)-3-chloro-2,2,5,5-tetramethyl-3-hexene and the thermodynamically less stable (E)-isomer, respectively. Alcoholate aggregates of different size (presumably, dimers and trimers or tetramers) are alternatively involved in these stereochemically distinct conversions, at least when potassium t-butoxide in t-butyl alcohol or tetrahydrofuran serves as a base/solvent system.