title: 4-(3-Azaniumylpropyl)morpholin-4-ium chloride hydrogen oxalate: an unusual example of a dication with different counter-anions.
abstract: The mixed organic-inorganic title salt, C7H18N2O(2+)·C2HO4(-)·Cl(-), forms an assembly of ionic components which are stabilized through a series of hydrogen bonds and charge-assisted intermolecular interactions. The title assembly crystallizes in the monoclinic C2/c space group with Z = 8. The asymmetric unit consists of a 4-(3-azaniumylpropyl)morpholin-4-ium dication, a hydrogen oxalate counter-anion and an inorganic chloride counter-anion. The organic cations and anions are connected through a network of N-H···O, O-H···O and C-H···O hydrogen bonds, forming several intermolecular rings that can be described by the graph-set notations R3(3)(13), R2(1)(5), R1(2)(5), R2(1)(6), R2(3)(6), R2(2)(8) and R3(3)(9). The 4-(3-azaniumylpropyl)morpholin-4-ium dications are interconnected through N-H···O hydrogen bonds, forming C(9) chains that run diagonally along the ab face. Furthermore, the hydrogen oxalate anions are interconnected via O-H···O hydrogen bonds, forming head-to-tail C(5) chains along the crystallographic b axis. The two types of chains are linked through additional N-H···O and O-H···O hydrogen bonds, and the hydrogen oxalate chains are sandwiched by the 4-(3-azaniumylpropyl)morpholin-4-ium chains, forming organic layers that are separated by the chloride anions. Finally, the layered three-dimensional structure is stabilized via intermolecular N-H···Cl and C-H···Cl interactions.
authors.affiliation: Centre for Metals-based Drug Discovery, Advanced Materials Division, Mintek, Private Bag X3015, Randburg, 2125, South Africa.
authors.forename: Telisha
authors.initials: T
authors.lastname: Traut-Johnstone
authors.affiliation: Centre for Metals-based Drug Discovery, Advanced Materials Division, Mintek, Private Bag X3015, Randburg, 2125, South Africa.
authors.forename: Frederik H
authors.initials: FH
authors.lastname: Kriel
authors.affiliation: Centre for Metals-based Drug Discovery, Advanced Materials Division, Mintek, Private Bag X3015, Randburg, 2125, South Africa.
authors.forename: Raymond
authors.initials: R
authors.lastname: Hewer
authors.affiliation: Research Centre for Synthesis and Catalysis, Department of Chemistry, University of Johannesburg, PO Box 524, Auckland Park 2006, South Africa.
authors.forename: D Bradley G
authors.initials: DB
authors.lastname: Williams
mesh_terms: D000838:Anions / Q000737:chemistry*; D003460:Crystallization; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D015394:Molecular Structure; D009025:Morpholines / Q000737:chemistry*; D009861:Onium Compounds / Q000737:chemistry*; D010070:Oxalates / Q000737:chemistry*
chemical_list: C000595911:4-(3-azaniumylpropyl)morpholin-4-ium chloride hydrogen oxalate; D000838:Anions; D009025:Morpholines; D009861:Onium Compounds; D010070:Oxalates
keywords: 4-(3-azaniumylpropyl)morpholin-4-ium; charge-assisted intermolecular interactions; crystal structure; hydrogen oxalate; organic–inorganic mixed salt