title: Crystal structure of 2-methyl-piperazine-1,4-diium bis-(hydrogen maleate).
abstract: In the title salt, C5H14N2 (2+)·2C4H3O4 (-), the asymmetric unit contains two independent 2-methyl-piperazinium dications, which comprise a racemic pair, and four hydrogen maleate monoanions. In the roughly planar hydrogen maleate anions, intra-molecular O-H⋯O hydrogen bonds generate S(7) rings. In the crystal, the four independent anions are linked to the 2-methyl-piperazinium cations through N-H⋯O hydrogen bonds, forming two-dimensional layered structures lying parallel to (001).
authors.affiliation: Laboratoire de chimie des Matériaux, Faculté des Sciences de Bizerte, Université de Carthage, 7021 Zarzouna Bizerte, Tunisia.
authors.forename: Intissar
authors.initials: I
authors.lastname: Wecharine
authors.affiliation: Department of Chemistry and Bioengineering, Tampere University of Technology, PO Box 541, 33101 Tampere, Finland.
authors.forename: Arto
authors.initials: A
authors.lastname: Valkonen
authors.affiliation: Laboratoire de chimie des Matériaux, Faculté des Sciences de Bizerte, Université de Carthage, 7021 Zarzouna Bizerte, Tunisia.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Rzaigui
authors.affiliation: Laboratoire de chimie des Matériaux, Faculté des Sciences de Bizerte, Université de Carthage, 7021 Zarzouna Bizerte, Tunisia.
authors.forename: Wajda
authors.initials: W
authors.lastname: Smirani Sta
keywords: 2-methyl­piperazine-1,4-diium; crystal structure; hydrogen bonding; hydrogen maleate
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