Poly[μ-(1,3-dihydroxypropan-2-olato)-potassium]

Abstract

Key indicators: single-crystal X-ray study; T = 173 K; mean (C-C) = 0.003 Å; R factor = 0.043; wR factor = 0.103; data-to-parameter ratio = 10.6.The asymmetric unit of the title compound, [K(C 3 H 7 O 3 )] n or K[H 2 gl] n , common name potassium glycerolate, contains half the K + cation and half of the glycerolate anion. The other half of the anion is generated through a mirror plane passing through the K atom, and a C, an H and an O atom of the glycerolate ligand. The K + ion is coordinated by the O atoms of the OH groups, leading to a six-membered chelate ring that adopts a very distorted boat conformation. The negatively charged O atom of the glycerolate anion, [H 2 gl À ], is found in the flagpole position and forms an ionic bond with the K + ion. The O atoms of the hydroxo groups are coordinated to two K + ions, whereas the negatively charged O atom is bonded to one K + ion. The K + ion is coordinated by three other symmetryrelated monodentate H 2 gl À ligands, so that each H 2 gl À ligand is bonded to two K + ions, and the potassium has a sevencoordinate environment. The H 2 gl À ligands are connected via a strong O-HÁ Á ÁO hydrogen bond and, together with the KÁ Á ÁO interconnections, form polymeric sheets which propagate in the directions of the a and b axes. Related literature

Glycerol as Ligand in Metal Complexes—A Structural Review

“…The crystals of 11 and 12 were obtained by adding glycerol to hot aqueous solutions of sodium hydroxide and potassium hydroxide, respectively. To be preserved, they must As part of their work on the design of catalysts for biodiesel production, Schatte's group elucidated in the early 2010s the crystallographic structures of two alkali metal glycerolates, solved as [Na(C 3 H 7 O 3 )] n (11) and [K(C 3 H 7 O 3 )] n (12), and in which glycerol acts as a [H 2 gly] − ligand [31,32]. In both cases, 11 and 12 exhibit polymeric structures, describing sheet-like organisations that propagate in the directions of the band c-axes, and a and b, respectively.…”