Clegg William, Tooke Duncan M
School of Chemistry, Newcastle University, Bedson Building, Newcastle upon Tyne NE1 7RU, England.
Acta Crystallogr B Struct Sci Cryst Eng Mater. 2013 Dec;69(Pt 6):603-12. doi: 10.1107/S2052519213025980. Epub 2013 Nov 1.
Reaction of 6-methyl-2-pyridone (Hmhp) with Na or K metal, or with Rb or Cs 2-ethylhexoxide, in an appropriate single or mixed solvent, yields a series of solvated polymeric complexes with the empirical formulae M(mhp)(H2O)2 [(1), M = Na; (2), M = K], M(mhp)(H2O) [(3), M = Rb; (4), M = Cs] and Cs(mhp)(ROH) [(5), R = Me; (6), R = Et]. All of the products have been crystallographically characterized and show sheet polymeric structures, except for a double-chain structure for (2). In all of the structures, mhp(-) and solvent molecules function as bridging ligands; two metal ions are bridged (μ2) by each solvent molecule in (1), (5) and (6), while (2) contains both μ2 and μ3 triple bridges, and (3) and (4) display highly unusual μ4 quadruple bridging of metal ions by water molecules. The pyridonate O atom bridges two or three metal ions in each case. Nitrogen is also involved in coordination to the heavier metals; it bonds to a single ion in (3) and (4), but has an almost unprecedented bridging role in (5) and (6). As a result of the extensive bridging by ligands, coordination numbers between 6 and 8 are achieved for the metal ions. In each structure, all solvent OH groups form hydrogen bonds to pyridonate O and, in some cases, N atoms. With one exception, these are the first reported pyridonate complexes of the alkali metals Na-Cs that do not also include transition metals.
在适当的单一或混合溶剂中，6-甲基-2-吡啶酮（Hmhp）与钠或钾金属，或与铷或铯的2-乙基己醇盐反应，生成一系列具有经验式M(mhp)(H2O)2 （[(1)，M = Na；(2)，M = K]）、M(mhp)(H2O) （[(3)，M = Rb；(4)，M = Cs]）和Cs(mhp)(ROH) （[(5)，R = Me；(6)，R = Et]）的溶剂化聚合物配合物。除了(2)具有双链结构外，所有产物均已通过晶体学表征并显示出层状聚合物结构。在所有结构中，mhp(-)和溶剂分子充当桥联配体；在(1)、(5)和(6)中，每个溶剂分子桥联（μ2）两个金属离子，而(2)同时包含μ2和μ3三桥，并且(3)和(4)显示水分子对金属离子具有高度不寻常的μ4四桥联作用。在每种情况下，吡啶酮O原子桥联两个或三个金属离子。氮也参与与较重金属的配位；它在(3)和(4)中与单个离子键合，但在(5)和(6)中具有几乎前所未有的桥联作用。由于配体的广泛桥联作用，金属离子的配位数达到6至8。在每个结构中，所有溶剂OH基团都与吡啶酮O形成氢键，在某些情况下还与N原子形成氢键。除了一个例外，这些是首次报道的不包含过渡金属的碱金属Na-Cs的吡啶酮配合物。
