Synthesis of 2-monofunctionalized 2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-diones

New (1R*,5S*)-2-R-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-diones containing the terminal carboxy or hydroxy group in the substituent R were synthesized by cyclocondensation of 4,5-dihydroxyimidazolidin-2-one with 1-R-ureas. Single-crystal X-ray diffraction analysis showed that 2-carboxyethyl-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-dione crystallizes as a racemate.     

Reaction of 1,3,5-tri-tert-butylbenzene with 2,4,6,8-tetraiodo-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-dione

Reactions of 1,3,5-tri-tert-butylbenzene with 2,4,6,8-tetraiodo-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-dione in acetic and trifluoroacetic acids involve substitution of one or two tert-butyl groups in the aromatic ring with formation of mono-, di-, and triiodo-substituted derivatives. No iodo derivatives are formed in acetonitrile.     

New Synthesis of 2,4,6,8-Tetramethyl-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-dione Using Etidronic Acid as a “Green” Catalyst

Russian Journal of Organic Chemistry - A new method has been developed for the synthesis of 2,4,6,8-tetramethyl-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-dione in 62% yield using etidronic acid...     

2,4,6,8-Tetraiodo-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-dione as a mild and convenient reagent for iodination of aromatic compounds

2,4,6,8-Tetraiodo-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-dione (tetraiodoglycoluril) is a convenient reagent for preparative iodination of benzene, alkylbenzenes, polycyclic hydrocarbons, aromatic amines, and phenol ethers in organic solvents under mild conditions.     

N-Silylation of 2,4,6-Trialkyl-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-diones

N-Trimethylsilyl derivatives of 2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-diones have been prepared for the first time and the electrophilic substitution reaction of the trimethylsilyl group has been studied.     

Three-dimensional structures and spectra of 2,6- and 2,8-diethyl-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-diones

Isomeric 2,6- and 2,8-diethyl-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-diones were obtained by the reaction of glyoxal with ethylurea, and their crystal structures and IR, Raman, and PMR spectra were studied.Translated from Khimiya Geterotsikiicheskikh Soedinenii, No. 7, pp. 937–941, July, 1991.     

3,7-二硝亚胺基-2,4,6,8-四硝基-2,4,6,8-四氮杂双环[3.3.0]辛烷结构与性能的量子化学研究

设计了一种新型高能量密度化合物--3,7-二硝亚胺基-2,4,6,8-四硝基-2,4,6,8-四氮杂双环[3.3.0]辛烷, 应用密度泛函理论(DFT)的B3LYP 方法在6-31G(d,p)基组水平上对该化合物进行了结构全优化, 并计算得到其红外(IR)光谱; 通过键级分析获得热解引发键的位置为N7-N22, 同时求得校正后的键离解能为91.47 kJ/mol. 采用Monte-Carlo方法预测该化合物的理论密度为2.16 g/cm³; 基于理论密度并结合等键反应及Kamlet-Jacobs公式预测了生成焓、爆速、爆压和爆热值分别为1219.94 kJ/mol, 10.43 km/s, 53.44 GPa和7407.84 J/g. 以上性能参数显示, 该目标化合物达到了高能量密度化合物的基本要求, 是一种潜在的含能材料. 同时给出了该化合物的逆合成路线.     

Chemistry of bicyclic ureas. 5. Synthesis of 2,4,6,8-tetraazabicyclo[3.3.0]-3-octanone-7-thiones

Conclusions A convenient method was developed for the synthesis of 2,4,6,8-tetraazabicyclo[3.3.0]-3-octanone-7-thiones by reacting the 4,5-dihydroxy- and 4,5-dimethoxy-2-imidazolidinethiones with substituted ureas.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1594–1597, July, 1980.     

Synthesis and separation of stereoisomeric 2,4,6,8-tetrasubstituted 3,7-dithia-1,5-diazabicyclo[3.3.0]octanes

Heterocyclization of hydrazine with aldehydes R-CHO (R = Me, Et, Prⁿ, Buⁿ, n-C₅H₁₁, Ph, 4-MeOC₆H₄, 3-Py) and H₂S leads to stereoisomeric 2,4,6,8-tetrasubstituted 3,7-dithia-1,5-diazabicyclo[3.3.0]octanes, which were separated by column chromatography. The trans-transoid-trans-configuration of tetramethyl(-ethyl,-propyl)-3,7-dithia-1,5-diazabicyclo-[3.3.0]octanes was inferred from the X-ray diffraction and ¹H and ¹³C NMR spectroscopic data.     

Heterocyclization of hydrazine with acetaldehyde and H2S

Hydrazine is regioselectively condensed with a mixture of acetaldehyde and H₂S at a temperature below −10 °C to form 2,4,6,8-tetramethyl-3,7-dithia-1,5-diazabicyclo[3.3.0]-octane. The reaction at 0 °C with the reverse order of mixing of the starting reagents affords 2,4,6-trimethyl(1,3,5-dithiazinan-5-yl)amine as the major product.     

Synthesis of chiral glycolurils from (<Emphasis Type="Italic">S</Emphasis>)-(+)- and (<Emphasis Type="Italic">R</Emphasis>)-(-)-1-<Emphasis Type="Italic">sec</Emphasis>-butyl-3-methylurea

Chiral dialkyl- and tetraalkylglycolurils have been obtained using chiral (S)-(+)- and (R)-(-)-1-sec-butyl-3-methylurea as starting materials. The diastereomer (S)-(+)-2,6-di-sec-butyl-4,8-dimethyl-2,4,6,8-tetraazabicyclo[3.3.0]-octane-3,7-dione was separated into stereoisomers, for the higher melting of which the absolute configuration was determined as (S,S,S,S) by X-ray structural analysis.     

Synthesis and study on 2,4,6,8-tetraaryl- 3,7-diazabicyclo[3.3.1]nonanes and their derivatives

1-Carbethoxy-2,4,6,8-tetraaryl-3,7-diazabicyclo[3.3.1] nonan-9-ones (1, 2) were synthesized and their 1H and 13C NMR data are reported. Chemical shifts and spectral assignments for 2,4,6,8-tetrakis(4-chlorophenyl)-3,7-diazabicyclo[3.3.1]nonan-9-one (3), 2,4,6,8-tetraphenyl-3-thia-7-azabicyclo[3.3.1]nonan-9-one (4) and 2,4,6,8-tetraaryl-3,7-diazabicyclo[3.3.1]nonanes (5-7) are also included.     

2,4,6,8-Tetraazabarbaralanes: Models for tetraazasemibullvalenes

3,7-Diethoxy-1,5-dimethyl-2,4,6,8-tetraaza-bicyclo[3.3.1]nona-2,6-diene (7), readily obtained from the corresponding urea derivative, can be oxidized to afford 3,7-diethoxy-1,5- dimethyl-2,4,6,8-tetraazabarbaralane (9) whose crystal structure corresponds to a localized molecule. On heating, 9 gives rise to 2-ethoxy-4,6-dimethyl-pyrimidine.     

Disproportionation of 6,8-Dialkyl-3-thia-2,4,6,8-tetraazabicyclo[3,3,0]octan-7-one 3,3-Dioxides under Conditions of Acid Hydrolysis and Acetylation

Acid hydrolysis and acetylation of 6,8-dialkyl-3-thia-2,4,6,8-tetraazabicyclo[3,3,0]octan-7-one 3,3-dioxides have been studied. 6,8-Dialkyl-3-thia-2,4,6,8-tetraazabicyclo[3,3,0]octan-7-one 3,3-dioxides disproportionate to 4,4'-sulfonyldiiminobis(1,3-dialkylimidazolidin-2-ones) and sulfamide when treated with acid at pH 1 or with acetyl chloride. The kinetics of the disproportionation have been studied.     

Kinetics and Mechanism of Exothermic First-stage Decomposition Reaction for 2,6-Dinitro-4,8-bis(2,2,2-trinitroethyl)-2,4,6,8-tetra-azabicyclo[3.3.1] nonane-3,7-dionel

Introduction 2,6-Dinitro-4,8-bis(2,2,2-trinitroethyl)-2,4,6,8-tetraazabicyclo[3.3.1] nonane-3,7-dionel is a typical cyclourea nitramine. Its crystal density is 1.94 g/cm3. The detonation velocity corresponding to ρ=1.920 g/cm3 is about 8957 m/s. It has the potential application as high explosive due to the above-mentioned high performance. Its preparation[1], properties[1] and hydrolytic behavior[2] have been reported. In the present paper, we report its kinetic parameters and mechanism of the exothermic first-stage decomposition reaction studied with DSC, TG-DTG and IR.     

Inter‐ring and endo anomeric effects,and hydrogen‐bonded supramolecular motifs in two 2,4,6,8‐tetraazabicyclo[3.3.0]octane derivatives

In 2,4,6,8‐tetrakis(4‐chlorophenyl)‐2,4,6,8‐tetraazabicyclo[3.3.0]octane, C₂₈H₂₂Cl₄N₄, the imidazolidine rings adopt envelope conformations, which are favoured by two equal endo anomeric effects. The molecule lies on a crystallographic twofold axis and molecules are linked into a three‐dimensional framework via two C—H...Cl hydrogen bonds. In 2,4,6,8‐tetrakis(4‐methoxyphenyl)‐2,4,6,8‐tetraazabicyclo[3.3.0]octane, C₃₂H₃₄N₄O₄, one of the methyl groups is disordered over two sets of sites and the same methyl group participates in an intermolecular C—H...O hydrogen bond, which in turn causes a considerable deviation from the preferred conformation. There are two unequal inter‐ring anomeric effects in the N—C—N groups. Molecules are linked into corrugated sheets by one C—H...π hydrogen bond and two independent C—H...O hydrogen bonds involving methoxy groups.     

Reaction of Alkyl 2-Bromoalkanoates with Zinc and Arylglyoxales

Methyl 2-bromo-2-methylpropionate reacts with zinc and arylglyoxals under conditions of Reformatsky reaction in ether-HMPA mixture to afford 1-aryl-4,4,8,8-tetramethyl-2,6-dioxabicyclo[3.3.0]octane-3,7-diones in 68-85% yield. Methyl 2-bromopropionate reacts with zinc and 4-bromophenylglyoxal in the same way giving the bicyclic product in 28% yield. The bromination of 1-(4-tolyl)-4,4,8,8-tetramethyl-2,6-dioxabicyclo[3.3.0]octane-3,7-dione with bromosuccinimide results in successive replacement of hydrogens in the tolyl moiety by bromine. The calculation of formation enthalpy for stereoisomers of compounds obtained in AM1 approximation predicts the highest stability for chair-type conformation with eclipsed position of substituents at C¹ and C⁵ atoms.     

New binuclear complex of bis(2,4,6,8-tetramethyl-2,4,6,8- tetraazabicyclo(3.3.0)octane-3,7-dione-<Emphasis Type="Italic">O,O</Emphasis>')-diaquatetrakis(nitrato-<Emphasis Type="Italic">O,O</Emphasis>')-dimanganese(II) monohydrate: Synthesis and crystal structure

The centrosymmetric binuclear manganese(II) nitrate complex with a bicyclic bis-carbamide, namely, 2,4,6,8-tetramethyl-2,4,6,8-tetraazabicyclo(3.3.0)octane-3,7-dione, or mebicar (Mk) [Mn(C₈H₁₄N₄O₂)(H₂O)(NO₃)₂]₂ · H₂O (I), has been synthesized for the first time. The structure of complex I has been solved (CCDC no. 1435139). Crystals of complex I are monoclinic, space group P2₁/c, a = 12.8108(11) Å, _b = 10.0662(2) Å, c = 18.6367(17) Å, β = 136.512(16)°, V = 1654.0(4) ų, ρcalcd = 1.659 g/cm³, Z = 2. Each manganese atom is coordinated to the two oxygen atoms of two Mk molecules related by the symmetry codes (1–x, 2–y, 1–z) and to two bidentate nitrate anions and one water molecule. The coordination polyhedron of the manganese atom is a strongly distorted pentagonal bipyramid. The Mn···Mn distance in the complex is 8.7261(9) Å.     

Reactions of diazaphospholes with phenyldiazomethane

Conclusions The action of 2-acetyl-5-methyl-1, 2, 3-diazaphosphole on phenyldiazomethane at –15°C in hexane leads to 2-acetyl-4-methyl-8-phenyl-1-phospha-2,3,7,8-tetraazabicyclo[3.3.0]octa-3,7-diene. The inverse action of phenyldiazomethane on 2-acetyl-5-methyl-1,2, 3-diazaphosphole at 0°C in ether gives 4, 11-diacetyl-6,7-dimethyl-2-phenyl-4,5,10,11-tetraaza-1,3-diphosphatricyclo[6.3.0.0^3,7]undeca-5, 9-diene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 412–418, February, 1986.     

New binuclear <Emphasis Type="Italic">bis</Emphasis>(2,4,6,8-tetramethyl-2,4,6,8-tetraazobicyclo(3.3.0)octane-3,7-dione-<Emphasis Type="Italic">O,O</Emphasis>')-tetraaqua-hexakis(nitrato-<Emphasis Type="Italic">O,O</Emphasis>')-disamarium(III) complex: Synthesis and crystal structure

The centrosymmetric binuclear complex of samarium(III) nitrate with bicyclic biscarbamide 2,4,6,8-tetramethyl-2,4,6,8-tetraazabicyclo(3.3.0)octane-3,7-dione, or mebicar (Mk) namely, [Sm(C₈H₁₄N₄O₂)(H₂O)₂(NO₃)₃]₂ (I) has been synthesized. Its crystal structure has been characterized (CIF file CCDC no. 1451436). Crystals of complex I are triclinic, space group P1 a = 9.8661(2) Å, b = 10.2913(3) Å, c = 10.9629(3) Å, α = 74.475(2)°, β = 67.802(2)°, γ = 67.570(2)°, V = 942.68(5) ų, ρcalcd = 2.01028 g/cm³, and Z = 1. The samarium atom is coordinated by the two oxygen atoms of two Mk molecules bonded via the symmetry center, three bidentate nitrate anions, and two water molecules. The coordination number of the samarium atom is 10, the coordination polyhedron of the metal atom is a decahedron and the Sm…Sm distance is 9.7904(4) Å.