Bialek Sebastian, Clemens Rebecca, Reiss Guido J
Institut für Anorganische Chemie und Strukturchemie, Lehrstuhl II: Material- und Strukturforschung, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany.
Acta Crystallogr Sect E Struct Rep Online. 2014 Feb 15;70(Pt 3):o312. doi: 10.1107/S1600536814002931. eCollection 2014 Mar 1.
The reaction of (di-methyl-phosphor-yl)methanamine (dpma) with oxalic acid in ethanol yielded the title solvated salt, C3H11NOP(+)·C2HO4 (-)·0.5C2H2O4. Its asymmetric unit consists of one dpmaH(+) cation, one hydrogen oxalate anion and a half-mol-ecule of oxalic acid located around a twofold rotation axis. The H atom of the hydrogen oxalate anion is statistically disordered over two positions that are trans to each other. The hydrogen oxalate monoanion is not planar (bend angle ∼16°) whereas the oxalic acid molecule shows a significantly smaller bend angle (∼7°). In the crystal, the components are connected by strong O-H⋯O and much weaker N-H⋯O hydrogen bonds, leading to the formation of layers extending parallel to (001). The structure was refined from a racemically twinned crystal with twin components in an approximate 1:1 ratio.
（二甲基磷酰基）甲胺（dpma）与草酸在乙醇中反应生成了标题溶剂化盐C₃H₁₁NOP⁺·C₂HO₄⁻·0.5C₂H₂O₄。其不对称单元由一个dpmaH⁺阳离子、一个草酸氢根阴离子和位于二次旋转轴周围的半个草酸分子组成。草酸氢根阴离子的H原子在彼此反式的两个位置上呈统计无序分布。草酸氢单阴离子不是平面的（弯曲角约16°），而草酸分子的弯曲角明显更小（约7°）。在晶体中，各组分通过强O—H⋯O和弱得多的N—H⋯O氢键相连，导致形成平行于（001）延伸的层。该结构是从一个外消旋孪晶晶体中精修得到的，孪晶组分比例约为1:1。
