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1,5-Dimethyl-3-[(3-phenyl-4,5-dihydro-1,2-oxazol-5-yl)methyl]-1H-1,5-benzodiazepine-2,4(3H,5H)-dione
Rachida Dardouri,Youssef Kandri Rodi,Nathalie Saffon,Lahcen El Ammari
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810042972
Abstract: The reaction of 3-allyl-1,5-dimethyl-1,5-benzodiazepine-2,4-dione and benzaldoxime leads to the title compound, C21H21N3O3. The molecular structure is built up from two fused six- and seven-membered rings linked to a chain including a five- and six-membered ring (isoxazoline and phenyl) via a methylene group. The seven-membered ring displays a boat conformation. The dihedral angle between the two six-membered rings is 74.3 (1)°.
p-nitrobenzoic acid promoted synthesis of 1,5-benzodiazepine derivatives
Varala, Ravi;Enugala, Ramu;Adapa, Srinivas R.;
Journal of the Brazilian Chemical Society , 2007, DOI: 10.1590/S0103-50532007000200008
Abstract: p-nitrobenzoic acid was found to be the versatile bronsted organic acid promoter among the carboxylic acids tested for the preparation of 1,5-benzodiazepine derivatives from a wide range of substituted o-phenylenediamines and ketones. the corresponding products were obtained in good isolated yields (62-92%) under mild conditions using acetonitrile as solvent at ambient temperature. further, the reagent could be easily recovered and reused.
The Formation of 2,2,4-Trimethyl-2,3-dihydro-1H-1,5-Benzodiazepine from 1,2-Diaminobenzene in the Presence of Acetone  [PDF]
Felix Odame,Phumelele Kleyi,Eric Hosten,Richard Betz,Kevin Lobb,Zenixole Tshentu
Molecules , 2013, DOI: 10.3390/molecules181114293
Abstract: In an attempt to synthesize a 2-substituted benzimidazole from the reaction of o-phenylenediamine and isophthalic acid in the presence of acetone and ethanol under microwave irradiation, a salt of the isophthalate ion and 2,2,4-trimethyl-2,3-dihydro-1 H-1,5-benzodiazepin-5-ium ion was obtained. The condensation of two moles of acetone with the amine groups resulted in the formation of the benzodiazepine which crystallized as an iminium cation forming a salt with the isophthalate anion. The formation of benzodiazepine was also confirmed by performing the reaction of o-phenylenediamine with excess acetone in ethanol under conventional heating conditions. The compounds were characterized by NMR, FTIR, HRMS and microanalysis as well as X-ray crystallography. The reaction mechanism leading to the formation of benzodiazepine is also discussed.
Evidence of Dirac insulator properties in poly 1,5-dihydro-1,5-diazocine diazene  [PDF]
R. Kevorkyants,V. Ligatchev,P. Wu
Physics , 2010,
Abstract: Existence of heteroaromatic graphene analog is predicted based upon periodic first principles density functional theory calculations. The new material, poly 1,5-dihydro 1,5-diazocine diazene, is a monolayered aromatic (planar) cross-linked polymer with cohesion energy - 6.03 eV/atom. Calculations reveal its Dirac insulator properties with narrow (~ 0.057 eV) and nearly direct band gap in close vicinity of \Gamma-point of Brillouin Zone. The predicted Fermi velocity of charge carriers ranges from ~3.41x105 m/s to ~1.63x106 m/s; thus effective mass of those could be up to ~2260 times lower than free electron one. These make proposed material a good alternative to graphene.
Bismuth (III) Salts Promoted and Ionic Liquid Assisted an Efficient and Environmentally Benign One-Pot Synthesis of 1,5-Benzodiazepine Derivatives  [PDF]
Atul Chaskar,Latika Patil,Kiran Phatangare,Vikas Padalkar,Santosh Takale
ISRN Organic Chemistry , 2011, DOI: 10.5402/2011/604348
Abstract: 1,5-Benzodiazepine derivatives were synthesized by the condensation reactions of o-phenylenediamine and ketones catalyzed by bismuth (III) salts under mild conditions. This method is easy, efficient, environment and eco-friendly, free of toxic catalysts, and gives good to excellent yields of 1, 5-benzodiazepines. 1. Introduction The synthesis of 1,5-benzodiazepines and their derivatives have attracted considerable attention of researchers, including pharmaceutical and organic synthetic chemists, in recent years because of their medicinal properties namely antianxiety, hypnotic, antidepressive, tranquilizing, antiinflammatory, anticonvulsant, antifeedant, antibacterial, and analgesic agents [1–4]. In addition, 1,5-benzodiazepines are valuable synthons used for the preparation of other fused ring compounds such as triazolo, oxazino or furano-benzodiazepines [5, 6]. Benzodiazepines derivatives are also used in industry as dyes for acrylic fibers in photography [7]. Due to their wide range of pharmacological activities and industrial and synthetic applications, the development of practical and green protocols continues to be a challenging endeavour in synthetic chemistry. In recent years, many methods for their preparation are reported in the literature. These include condensation reactions of o-phenylenediamine with α, β-unsaturated carbonyl compounds [8], β-haloketones [9], β-aminoketones [10] or ketones promoted by BF3·OEt2 [11], NaBH4 [12], polyphosphoric acid or SiO2 [13], ceric ammonium nitrate (CAN) [14], MgO/POCl3 [15], Yb(OTf)3 [16], Al2O3/P2O5 or AcOH under microwave conditions [17], Amberlyst-15 in ionic liquid [18], CeCl3/7H2O/NaI supported on silica gel [19], InBr3 [20], 1-butyl-3-methylimidazolium bromide ([bmim]Br) [21], Sc(OTf)3 [22], and Nb(Cl)3 [23]. However, many of these methodologies have one or more shortcomings, such as long reaction time, poor yields of the products, drastic reaction conditions, occurrence of several side products, expensive reagents, high catalyst loading, and tedious workup procedures. Bismuth (III) salts have emerged in the recent years as “eco-friendly” reagents suitable for green chemistry. They have received considerable attention as mild Lewis acids [24–27] for an array of organic transformations because the catalysts are inexpensive, relatively nontoxic, moisture and air tolerant, environmentally benign, and commercially available. Ionic liquid is used as an alternative to traditional solvents for organic reactions particularly in the area of green chemistry. Thus, considering the advantages and applications
Efficient TCT-catalyzed Synthesis of 1,5-Benzodiazepine Derivatives under Mild Conditions  [PDF]
Chun-Wei Kuo,Chun-Chao Wang,Veerababurao Kavala,Ching-Fa Yao
Molecules , 2008, DOI: 10.3390/molecules13092313
Abstract: 2,4,6-Trichloro-1,3,5-triazine (TCT) efficiently catalyzed the condensation reactions between 1,2-diamines and various enolizable ketones to afford 1,5-benzodiazepines in good to excellent yields. Simple and mild reaction conditions, the use of a cheap catalyst and easy workup and isolation are notable features of this method.
2-Methyl-2,4-di-4-pyridyl-2,3-dihydro-1H-1,5-benzodiazepine acetic acid solvate
Shi-Chao Wang,Qiu-Fei Hou,Shi-Mei Jiang
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809049836
Abstract: In the title compound, C20H18N4·CH3COOH, the benzene ring forms dihedral angles of 81.34 (11) and 54.32 (11)° with the two pyridine rings. In the crystal, intermolecular O—H...N hydrogen bonding links one 1,5-benzodiazepine molecule and one acetic acid solvent molecule into a dimer. These dimers, related by translation along the b axis, are further linked into chains via weak intermolecular N—H...N hydrogen bonds.
3-(2,4-Dichlorophenyl)-5-(4-fluorophenyl)-2-phenyl-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine  [cached]
Ju Liu,Zhi-Qiang Cai,Yang Wang,Yu-Li Sang
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812023641
Abstract: In the title compound, C25H13Cl2F4N3, there are four planar systems, viz. three benzene rings and a pyrazolo[1,5-a]pyrimidine system [r.m.s. deviation = 0.002 ]. The dihedral angle between the dichlorophenyl ring and the unsubstituted phenyl ring is 69.95 (5)°, while that between the fluorophenyl ring and the unsubstituted phenyl ring is 7.97 (10)°. The crystal packing is dominated by van der Waals interactions. A Cl...Cl interaction of 3.475 (3) also occurs.
3-(4-Fluorophenyl)-2-(4-pyridyl)pyrido[2,3-b]pyrazine
Pierre Koch,Dieter Schollmeyer,Stefan Laufer
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809037970
Abstract: In the crystal structure of the title compound, C18H11FN4, the pyridopyrazine ring makes dihedral angles of 34.67 (7) and 52.24 (7)° with the 4-fluorophenyl and pyridine rings, respectively. The 4-fluorophenyl ring makes a dihedral angle of 59.56 (9)° with the pyridine ring.
2-(4-Fluorophenyl)-3-(4-pyridyl)pyrido[2,3-b]pyrazine
Pierre Koch,Dieter Schollmeyer,Stefan Laufer
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809037295
Abstract: In the crystal structure of the title compound, C18H11FN4, the pyridopyrazine system makes dihedral angles of 45.51 (7) and 44.75 (7)° with the attached 4-fluorophenyl ring and the pyridine ring, respectively. The 4-fluorophenyl ring makes a dihedral angle of 54.54 (8)° with the pyridine ring. The pyridine ring part of the pyridopyrazine ring and the pyrazine ring of two c-glide-plane-related molecules form π–π interactions. The angle between the planes is 2.09 (7)° and the distance between the centroids is 3.557 (1) .
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