Experimental Crystal data

R factor = 0.036; wR factor = 0.091; data-to-parameter ratio = 15.4. In the title compound, C26H28FN5O3, the morpholine ring adopts a chair conformation. The piperazine ring is puckered [QT = 0.5437 (15) Å, = 8.89 (15) and ’ = 357.2 (11) ]. The 1,6-dihydropyridazine ring makes dihedral angles of 28.03 (7) and 77.46 (7) with the phenyl and benzene rings, respectively. In the crystal, molecules are linked along the c axis by C— H O interactions and are flattened parallel to the ac plane. C–H interactions also contribute to the stability of the structure. Related literature For the pharmacological effects, biological activity and synthesis of 3(2H)-pyridazinones, see: Şüküroğlu et al. 2006; Brogden 1986. For bond-length data, see: Allen et al. (1987). For ring conformational analysis, see: Cremer & Pople (1975). For the quantum mechanical CNDO/2 approximation, see