In the crystal structure of the title compound, C(21)H(18)FN(5), the pyridopyrazine ring system forms dihedral angles of 33.27 (7) and 48.69 (9)° with the 4-fluoro-phenyl and pyridine ring, respectively. The dihedral angle of the 4-fluoro-phenyl and pyridine rings is 57.45 (8)°. The crystal packing is characterized by an inter-molecular N-H⋯N hydrogen bond.

A set of 42 molecules with N-F, O-F, N-Cl, P-F, and As-F bonds has been investigated in the search for potential bond anomalies, which lead to reverse bond length-bond strength (BLBS) relationships. The intrinsic strength of each bond investigated has been determined by the local stretching force constant obtained at the CCSD(T)/aug-cc-pVTZ level of theory. N-F or O-F bond anomalies were found ...

In the title compound, C(11)H(7)F(2)N, the fluoro-benzene and the 2-fluoro-pyridine rings are oriented at a dihedral angle of 37.93 (5)°. In the crystal, only van der Waals inter-actions occur.

The crystal structure of the title compound, C(15)H(11)FN(6)S, forms a three-dimensional network stabilized by π-π inter-actions between the imidazole core and the tetra-zole ring of the tetra-zolopyridine-unit; the centroid-centroid distance is 3.627 (1) Å. The crystal structure also displays bifurcated N-H⋯(N,N) hydrogen bonding and C-H⋯F inter-actions. The former involve the NH H atom of the...

In the title compound, C(17)H(12)F(2)N(2)OS, the planar thia-zole ring (r.m.s. deviation = 0.012 Å) makes dihedral angles of 15.08 (9) and 81.81 (6)° with the 4-fluoro-phenyl and 2-fluoro-phenyl rings, respectively. The 2-fluoro-phenyl ring is disordered over two orientations with site-occupancy factors of 0.810 (3) and 0.190 (3). The structure contains inter-molecular C-H⋯O hydrogen bonds.

The asymmetric unit of the title monohydrated salt, 2C26H28F2N2 (2+)·4Cl(-.)H2O, consists of a 1-[bis-(4-fluoro-phen-yl)meth-yl]-4-[(2Z)-3-phenyl-prop-2-en-1-yl]piperazine-1,4-diium cation with a diprotonated piperizine ring in close proximity to two chloride anions and a single water mol-ecule that lies on a twofold rotation axis. In the cation, the piperazine ring adopts a slightly distorted ...

In the title compound, [Cu(C(8)F(4)O(4))(C(5)H(5)N)(3)](n), the Cu(II) atom, lying on a twofold rotation axis, is five-coordinated by two O atoms from two tetra-fluoro-terephthalate ligands and three N atoms from three pyridine ligands in a distorted trigonal-bipyramidal geometry. Adjacent Cu(II) atoms are connected via the bridging tetra-fluoro-terephthalate ligands into a one-dimensional chai...

The mol-ecular and crystal structures of the title compound, C(16)H(14)FN(3)O(2), are stabilized by intra-molecular N-H⋯O and inter-molecular O-H⋯O hydrogen bonds. The existence of non-classical intra-molecular C-H⋯N hydrogen bonds provides a dihedral angle between the fluoro-substituted benzene and pyrimidinone rings of 7.9 (1)°.