Abstract Nitrogen‐heterocycle‐based covalent organic frameworks (COFs) are considered promising candidates for the overall photosynthesis of hydrogen peroxide (H 2 O ). However, effects relative nitrogen locations remain obscured and photocatalytic performances COFs need to be further improved. Herein, a collection functionalized by various diazines including pyridazine, pyrimidine, pyrazine ha...

In the title compound, C(18)H(16)N(2)O(2), the central pyridazine ring forms dihedral angles of 77.08 (5)° and 84.62 (5)° with the two benzene rings. The dihedral angle between the two benzene rings is 68.18 (4)°. A very weak intra-molecular C-H⋯N hydrogen bond and an intra-molecular C-H⋯π inter-action occur. The crystal structure is stabilized by weak inter-molecular C-H⋯O hydrogen bonds and w...

The elaboration of the first organophosphorus-catalyzed diaza-Wittig reaction is reported. This catalytic reaction is applied to the synthesis of substituted pyridazine and phthalazine derivatives bearing electron-withdrawing groups with good to excellent yields from substrates containing a diazo functionality as the starting material and a phospholene oxide as the catalyst.

The isomerization energies of 1,2- and 1,3-diazacyclobutadiene, pyrazole and imidazole, and pyridazine and pyrimidine are 10.6, 9.4, and 20.9 kcal/mol, respectively, at the BP86/TZ2P level of theory. These energies are analyzed using a Morokuma-like energy decomposition analysis in conjunction with what we have called turn-upside-down approach. Our results indicate that, in the three cases, the...

In the title compound, C(22)H(19)F(3)N(2)O(3), the benzene rings of the trifluoro-methyl-phenyl and benzoyl-phenyl groups form dihedral angles of 41.89 (10) and 67.44 (10)°, respectively, with the pyridazine ring. The methyl-propanoate group is nearly coplanar with the attached benzene ring [dihedral angle = 3.9 (2)°]. The trifluoro-methyl group is disordered over two positions; the site-occupa...

The nine-membered fused-ring system of the title pyridazine derivative, C(13)H(12)N(4)O(4)S, is approximately planar (r.m.s. deviation 0.027 Å), and the benzene ring of the phenyl-sulfamide substituent is aligned at 43.5 (1)° to the fused-ring system. The amine group of the sulfonamide substituent forms an N-H⋯O hydrogen bond to the ketonic O atom of two neigboring mol-ecules to generate a chai...

In the title compound, C(11)H(8)Cl(2)N(2)O, the benzene and pyridazine rings are tilted by 8.6 (1)° relative to each other. In the crystal, pairs of inter-molecular N-H⋯O hydrogen bonds form centrosymmetric dimers. π-π contacts with centroid-centroid distances of 3.698 (2) and 3.751 (1) Å and halogen-halogen inter-actions [3.379 (1) Å] also stabilize the structure.

Trinuclear copper(I) and silver(I) pyrazolates {[3,5-(CF3)2Pz]M}3 (M = Cu and Ag) react with pyridazine to give neutral, tetranuclear metallacycles with a para-cyclophane core whereas benzo[c]cinnoline fails to break the cyclic pyrazolate trimers under similar conditions, and affords a metalla-propellane featuring both two- and three-coordinate metal sites.