Diaqua­dichloridobis[quinazolin-4(1H)-one-κN 3]copper(II)

In the title complex, [CuCl2(C8H6N2O)2(H2O)2], the CuII ion is located on an inversion center and is octahedrally coordinated by two N atoms of the 1H-quinazolin-4-one ligand, two chloride ligands and two aqua ligands. The axial Cu—O distances are significantly longer [2.512 (2) Å], than the Cu—N [2.022 (2) Å] and Cu—Cl [2.3232 (4) Å] distances as a result of Jahn–Teller distortion. Aqua ligands are involved in intra- and inter­molecular hydrogen bonding, and N—H⋯O inter­molecular hydrogen bonds are formed between the organic ligands. In addition, weak π–π inter­actions are observed between the benzene rings of the ligand [centroid–centroid distance = 3.678 (1) Å]

Diaqua­dichloridobis[quinazolin-4(1H)-one-κN 3]nickel(II)

In the title complex, [NiCl2(C8H6N2O)2(H2O)2], the NiII ion is located on an inversion center and is six-coordinated by two N atoms of 1H-quinazolin-4-one ligands, two chloride ions and two water mol­ecules. The water mol­ecules are involved in intra- and inter­molecular O—H⋯O and O—H⋯Cl hydrogen bonding. Inter­molecular N—H⋯O and N—H⋯Cl hydrogen bonds are formed between ligands. In addition, weak π–π inter­actions are observed between the benzene rings of the ligands [centroid–centroid distance = 3.580 (3) Å]. The inter­molecular hydrogen bonds and π–π inter­actions lead to the formation of a three-dimensional supra­molecular network

2-{2-[2-(1,3-Dioxoisoindol-2-yl)eth­oxy]eth­yl}isoindole-1,3-dione

In the mol­ecule of the title compound, C20H16N2O5, the phthalimide fragments are almost planar, with r.m.s. deviations of 0.018 and 0.020 Å, and make a dihedral angle of 53.64 (3)°. The mol­ecular and crystal structures are stabilized by a weak inter­molecular C—H⋯O, C—H⋯π and C=O⋯π [2.883 (1) Å] inter­actions and aromatic π–π stacking inter­actions with a centroid–centroid distance of 3.6189 (7) Å

2,3-Dihydro­pyrrolo­[2,1-b]quinazoline-9(1H)-thione

In the crystal, mol­ecules of the title compound, C11H10N2S, are connected by C—H⋯N inter­actions around threefold axes. Furthermore, they form stacks along the c axis showing π–π inter­actions between pyrimidine rings [centroid–centroid distance = 3.721 (1) Å]. The central ring is essentially planar with an r.m.s. deviation of 0.007 Å. The five-membered ring adopts an envelope conformation with the flap atom deviating by 0.241 (4) Å from the mean plane (r.m.s. deviation = 0.002 Å) through the other four ring atoms

11-(2-Oxopyrrolidin-1-ylmeth­yl)-1,2,3,4,5,6,11,11a-octa­hydro­pyrido[2,1-b]quinazolin-6-one dihydrate

In the crystal structure of the title compound, C17H21N3O2·2H2O, water mol­ecules are mutually O—H⋯O hydrogen bonded and form infinite chains propagating along the b axis. Neighboring chains are linked by the quinazoline mol­ecules by means of O—H⋯O=C hydrogen bonds, forming a two–dimensional network

Математическое моделирование зажигания растительного покрова в результате разрыва газопровода

В данной работе представлена математическая модель и численные результаты зажигания полога леса в результате разрыва газопровода с образованием "огненного шара" с учетом структурных особенностей и характеристик лесного горючего материала, а также особенности среды, в которой происходит тепловое излучение. Проблема взрывов в нефтехимической промышленности с образованием ОШ является сегодня актуальной для многих стран, включая и РФ. Разработана компьютерная программа, которая используется для определения безопасных расстояний от объектов повышенной опасности (ОПО).This paper presents a mathematical model and results of calculations of the ignition of forest canopy as a result of the gas pipeline rupture with the formation of a fireball taking into account the structural features and characteristics of forest fuel material, as well as the features of the environment in which thermal radiation occurs. The problem of explosions in the petrochemical industry with the formation of the Fire Ball is relevant for many countries now, including the Russian Federation. A computer program has been developed that is used to determine the safe distances from high-risk objects

(E)-3-Propoxymethyl­idene-2,3-dihydro-1H-pyrrolo[2,1-b]quinazolin-9-one monohydrate

The title compound, C15H16N2O2·H2O, was synthesized via the alkyl­ation of 3-hydroxy­methyl­idene-2,3-dihydro-1H-pyrrolo[2,1-b]quinazolin-9-one with n-propyl iodide in the presence of sodium hydroxide. The organic mol­ecule and the water mol­ecule both lie on a crystallographic mirror plane. In the crystal structure, inter­molecular O—H⋯O and O—H⋯N hydrogen bonds link the components into extended chains along [100]

3-Benzyl-6-(2-chloro­benzo­yl)-1,3-benzoxazol-2(3H)-one

In the title compound, C21H14ClNO3, the benzoxazolone ring system is planar (r.m.s. deviation = 0.022 Å) and forms dihedral angles of 75.38 (10) and 65.92 (13)° with the mean planes of the chloro­benzoyl (r.m.s. deviation = 0.045 Å, excluding O atom) and benzyl (r.m.s. deviation = 0.023 Å) groups. The observed structure is stabilized by weak C—H⋯O hydrogen bonds and weak inter­molecular C—H⋯π inter­actions

[2-(3,4-Dimethoxyphenyl)ethyl](3-{N-[2-(3,4-dimethoxyphenyl)ethyl]carbamoyl}propyl)azanium chloride dihydrate

The asymmetric unit of the title hydrated salt, C24H35N2O5+·Cl−·2H2O, contains one organic cation that has its protonation site at the amine function, one chloride anion and two lattice water molecules. In the crystal, one pair of lattice water molecules and two chloride anions form a four-membered centrosymmetric hydrogen-bond cycle. In addition, O—H...O, N—H...O and N—H...Cl hydrogen bonds involving the N—H groups, the water molecules and the C=O group are observed. As a result, a hydrogen-bonded layer parallel to (100) is formed. The thickness of such a layer corresponds to the length of the a axis [21.977 (3) Å]

Metal halide coordination compounds with quinazolin-4(3H)-one

Three coordination compounds of quinazolin-4(3H)-one (quinoz; C8H6N2O) with divalent group 12 halides are reported. In all complexes, coordination occurs via the nitrogen atom ortho to the quinazolinone carbonyl group. In the two chain polymers with composition [MX2(quinoz)], viz. (M = Cd, X = Br), catena-poly[[[quinazolin-4(3H)-one-κN3]cadmium(II)]-di-μ-bromido], [CdBr2(C8H6N2O)]n (I), and M = Hg, X = Cl, catena-poly[[[quinazolin-4(3H)-one-κN3]mercury(II)]-di-μ-chlorido], [HgCl2(C8H6N2O)]n (II), the divalent cations are five-coordinate, with four bridging halide and one terminal quinoz ligand. The CdII atom in (I) has an almost trigonal–bipyramidal coordination environment, whereas the HgII atom in (II) has a more distorted coordination environment. Likewise, the halide bridges in (II) are significantly more asymmetric than in (I). In both (I) and (II), quinoz ligands at adjacent cations along each strand are oriented in opposite directions, and the organic ligands of neighboring strands interdigitate with resulting π–π interactions. In contrast to the halide-bridged chain polymers (I) and (II), the adduct of quinoz with CdI2 is the tetrahedral complex [CdI2(quinoz)2], diiodidobis[quinazolin-4(3H)-one-κN3]cadmium(II), [CdI2(C16H12N4O2)], (III). The CdII atom in this discrete complex is located on a twofold rotation axis. Disorder in (III) is reflected in an alternative minority orientation of the molecules for which the iodine sites closely match the position of the majority orientation. In view of the low site occupancy of only 0.0318 (8) Å, only the CdII position for this alternative orientation was taken into account during refinement. In all three compounds, classical N—H...O hydrogen bonds with donor–acceptor distances of ca 2.9 Å occur; they link the polymer chains in (I) and (II) into di-periodic networks and connect adjacent discrete complexes in (III) to mono-periodic strands