Hydrogen-bonded neutral and anionic lamellar networks: Crystal structures of bis(O,O′,O″-hydroorotato)disilver(i) dihydrate, potassium hydroorotate and rubidium hydroorotate. Ab initio calculations on orotic acid and the hydroorotate anion
作者:Somer Bekiroglu、Olof Kristiansson
DOI:10.1039/b110386p
日期:——
The complex adducts of silver(I) (1), potassium(I) (2) and rubidium(I) (3) with the hydroorotate (2,6-dioxo-1,2,3,6-tetrahydropyrimidine-4-carboxylate) anion have been prepared, and their structures determined by X-ray diffraction. Crystals of bis(O,Oâ²,Oâ³-hydroorotato)disilver(I) dihydrate (1) consist of a polymeric structure which is based on bis(hydroorotato-O,Oâ²) bridged dimers, analogous to those found in many O,Oâ²-bridged silver carboxylates. Extensive hydrogen-bonding and secondary carbonyl-Oâ¯Ag interactions result in infinite, neutral sheets with an interplanar spacing of 3.085 Ã
. Crystals of 2 (KC5H3N2O4)
consist of a lamellar structure with infinite anionic sheets parallel to the crystallographic (100) plane. The distance between two adjacent sheets is 3.417 Ã
and the K+ cations are situated between the sheets with slightly distorted square antiprismatic geometries. Compound 3 (RbC5H3N2O4) is essentially isostructural with the potassium analogue with the interplanar spacing increased to 3.600 Ã
. Ab initio calculations on orotic acid and the hydroorotate anion were performed. The optimized geometries and harmonic vibrational frequencies were computed using density functional theory B3LYP/6-31G(d) model chemistry. 1H and 13C NMR chemical shifts were calculated at the HF/6-311++(2d,2p) and B3LYP/6-311++G(2d,2p) levels, and compared with experimental values.
银(I) (1)、钾(I) (2) 和铷(I) (3) 与氢乳清酸盐(2,6-二氧代-1,2,3,6-四氢嘧啶-4-羧酸盐)的复合加合物)阴离子已被制备,并通过X射线衍射确定了它们的结构。双(O,O‐2,O‐3-氢乳清)二银(I)二水合物晶体 (1) 由基于双(氢乳清-O,O‐2) 桥联二聚体的聚合结构组成,类似于发现的那些存在于许多O,O-桥联的羧酸银中。广泛的氢键和二级羰基-O-Ag 相互作用产生无限的中性片,晶面间距为 3.085 ×。 2 (KC5H3N2O4) 的晶体
由层状结构组成,具有平行于晶体 (100) 平面的无限阴离子片。两个相邻片材之间的距离为 3.417 ×,K+ 阳离子位于具有稍微扭曲的方形反棱镜几何形状的片材之间。化合物 3 (RbC5H3N2O4) 与钾类似物基本上是同构的,晶面间距增加到 3.600 ×。对乳清酸和氢乳清酸阴离子进行从头计算。使用密度泛函理论 B3LYP/6-31G(d) 模型化学计算优化的几何形状和谐波振动频率。计算HF/6-311++(2d,2p)和B3LYP/6-311++G(2d,2p)水平的1H和13C NMR化学位移,并与实验值进行比较。