Wechselwirkungen in Kristallen 62 [1, 2] Kristallisation und Strukturbestimmung von 2,5-Bis(trimethylsilyl)-p-benzochinon und von 2,5-Bis(trimethylsilyl)hydrochinon-natrium-bis(dimethoxyethan), einem Polymer-Strang mit Chelat-überkappten Wasserstoffbrücken (⊖O···HO)Na⊕(DME)2/ Interactions in Crystals, 62 [1, 2] Crystallization and Structure Determination of 2,5-Bis(trimethylsilyl)-p-benzoquinone and of 2,5-Bis(trimethylsilyl)hydroquinone Sodium Bis(dimethoxyethane), a Polymer String with Chelate-Capped Hydrogen Bridges (⊖O···HO)Na⊕(DME)2

Abstract

From the electron and proton transfer equilibria network of quinones in solution a novel intermediate can be prepared by deprotonation of 2,5-bis(trimethylsilyl)hydroquinone to its monoanion using sodium metal. The sodium salt crystallizes in polymer strings connected via O⊖···(H)O hydrogen bridges, which are capped additionally by twofold dimethoxy-ethanesolvated Na⊕ countercations. The single crystal structure determination reveals one of the shortest O⊕ ··· HO distances observed so far of only 246 pm. MNDO calculations further confirm the assignment of hydroquinone monoanion building blocks in the polymer chain. For structural comparison as well as for attempts of its sodium reduction, 2,5-bis(trimethylsilyl)-p- benzoquinone has been synthesized. Its single crystal structure is reported, which does not show any cyanine distortion.