title: Crystal structure of 2-di-methyl-amino-1-eth-oxy-carbonyl-3-methyl-3,4,5,6-tetra-hydro-pyrimidin-1-ium tetra-phenyl-borate.
abstract: The asymmetric unit of the title salt, C10H20N3O2 (+)·C24H20B(-), contains two cations and two tetra-phenyl-borate ions. The C-N bond lengths in the central CN3 unit of the guanidinium ions range between 1.323 (2) and 1.381 (2) Å, indicating partial double-bond character. The central C atoms are bonded to the three N atoms in a nearly ideal trigonal-planar geometry and the positive charge is delocalized in the CN3 plane. The cationic six-membered rings are nonplanar, the dihedral angles between the N/C/N and C/C/C planes ranging from 45.8 (1) to 53.6 (1)°. In the crystal, C-H⋯π inter-actions are present between the guanidinium H atoms and the phenyl rings of the tetra-phenyl-borate ions. The phenyl rings form aromatic pockets, in which the guanidinium ions are embedded.
authors.affiliation: Fakultät Chemie/Organische Chemie, Hochschule Aalen, Beethovenstrasse 1, D-73430 Aalen, Germany.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Tiritiris
authors.affiliation: Fakultät Chemie/Organische Chemie, Hochschule Aalen, Beethovenstrasse 1, D-73430 Aalen, Germany.
authors.forename: Willi
authors.initials: W
authors.lastname: Kantlehner
keywords: C—H⋯π inter­actions; crystal structure; cyclic guanidinium salt; tetra­phenyl­borate