Kavitha Channappa N, Kaur Manpreet, Jasinski Jerry P, Yathirajan Hemmige S
Department of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India.
Department of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA.
Acta Crystallogr Sect E Struct Rep Online. 2014 May 31;70(Pt 6):o717-8. doi: 10.1107/S1600536814011726. eCollection 2014 Jun 1.
In the title salt, C6H13N2O(+)·C6H2N3O7 (-) (systematic name: 4-acetyl-piperazin-1-ium 2,4,6-tri-nitro-phenolate), the piperazin-1-ium ring has a slightly distorted chair conformation. In the picrate anion, the mean planes of the two o-NO2 and p-NO2 groups are twisted with respect to the benzene ring by 15.0 (2), 68.9 (4) and 4.4 (3)°, respectively. In the crystal, N-H⋯O hydrogen bonds are observed, linking the ions into an infinite chain along [010]. In addition, weak cation-anion C-H⋯O inter-molecular inter-actions and a weak π-π stacking inter-action between the benzene rings of the anions, with an inter-centroid distance of 3.771 (8) Å, help to stabilize the crystal packing, giving an overall sheet structure lying parallel to (100). Disorder was modelled for one of the O atoms in one of the o-NO2 groups over two sites with an occupancy ratio of 0.57 (6):0.43 (6).
在标题盐C6H13N2O(+)·C6H2N3O7 (-)（系统名称：4-乙酰基哌嗪-1-鎓2,4,6-三硝基苯酚盐）中，哌嗪-1-鎓环具有轻微扭曲的椅式构象。在苦味酸盐阴离子中，两个邻位硝基和对位硝基基团的平均平面相对于苯环分别扭转了15.0 (2)°、68.9 (4)°和4.4 (3)°。在晶体中，观察到N-H⋯O氢键，将离子沿[010]连接成无限链。此外，弱的阳离子-阴离子C-H⋯O分子间相互作用以及阴离子苯环之间的弱π-π堆积相互作用（质心间距为3.771 (8) Å）有助于稳定晶体堆积，形成平行于(100)的整体片状结构。对一个邻位硝基基团中的一个O原子在两个位置上进行了无序建模，占有率比为0.57 (6):0.43 (6)。
