Regioselectivity of Oxysulfenylations of Cycloocta-1,5-diene

The regioselectivity of transannular O-heterocyclization of cycloocta-1,5-diene ( 1 ) with phenylsulfenyl chloride and methanol or water, respectively, is determined by the oxy-component which acts as nucleophilic partner in the electrophilic three component reaction. The thermodynamically more stable endo, endo-2,6-bis(phenylsulfenyl)-9-oxabicyclo[3.3.1]nonane ( 2 ) is formed almost exclusively in methanol while the isomeric 9-oxabicyclo[4.2.1]nonane ( 3 ) is favored under kinetic control in the presence of water. The oxidation of 2 or 3 yields the bissulfones 4 and 5 , respectively.     

Stereoselective reduction of (±)-bicyclo[3.3.1]nonane-2,6-dione by microorganisms

The biotransformation of (±)-bicyclo[3.3.1]nonane-2,6-dione by Aspergillus niger and Glomerella cingulata was investigated. The diketone was reduced to the ketoalcohol 2-endo-hydroxy-bicyclo[3.3.1]nonane-6-one and the diol endo,endo-bicyclo[3.3.1]nonane-2,6-diol respectively. Endo,endo-bicyclo[3.3.1]nonane-2,6-diol and ketoalcohols produced by G. cingulata had high optical purity, on the other hand, reduction by A. niger yielded optically active (-)-(1R, 2S, 5R, 6S)-bicyclo[3.3.1]nonane-2,6-diol(99·9% e.e.). © 1998 SCI     

Polymerization of α,β-unsaturated carbonyl monomers initiated by 9-borabicyclo [3.3.1] nonane

9-Borabicyclo[3.3.1]nonane (9-BBN) initiated the polymerization of α,β-unsaturated carbonyl monomers such as ethyl acrylate (EA) without an oxidant at low temperatures (to −90°C) under argon. Hydroquinone and 2,6-di-tert-butyl-p-cresol had little effect on the polymerization, indicating that the propagating chain end is not a free radical. The rate of polymerization was found to be proportional to [9-BBN]^1.0 and [EA]^1.5. Electron spin resonance measurements using 5,5-dimethyl-1-pyrroline-N-oxide as a spin trap showed the absence of any radical species under polymerization conditions. No copolymerization of EA with styrene occurred. On the basis of the results obtained, this polymerization was assumed to proceed via a non-radical mechanism.     

双环硝胺类含能化合物的合成进展

综述了国内外双环硝胺类含能化合物的合成进展,主要包括醛胺缩合法合成双环[3.3.1]壬烷衍生物、乌洛托品与亲电试剂反应合成双环[3.3.1]壬烷衍生物、以及含单、双环硝基脲硝胺类含能化合物的合成方法。指出含有单、双环硝基脲的硝胺类含能化合物具有非常高的密度,适合于作为高能量密度材料的基础单元结构;双环[3.3.1]壬烷衍生物合成中的醛胺缩合法为八元双环含能化合物的合成提供了新途径。     

Push-pull-Butadiene. XII. Darstellung von Hetrocyclen aus 2,6-Bis[bis(alkylthio)methylen]cyclohexylidenmalononitrilen

Preperations of Heterocycles by using of 2,6-Bis[bis(alkylthio)methylene]cyclohexylidenemalononitriles . 2,6-Bis[bis(alkylthio)methylene]cyclohexylidenemalonitriles 1 react with alkanethioles to give 1,3-bis(alkylthio)-5-[bis(alkylthio)methylene]-5,6, #7,8-tetrahydro-isoquinoline-4-carbonitriles 2 . Treatment of 1 with hydrogen bromide yields 4,6,7,9-tetrakis(alkylthio)-2,3-dihydro-5,8-diaza-phenalenes 3 . On the other hand, 1 can be converted with bromine to 6,9-bis(alkylthio)-4,7-dibromo-2,3-dihydro-5,8-diaza-phenalenes 5 . However, the reaction of 1 and N-bromosuccinimide afforded 2,6-bis[bis(alkylthio)methylene]-3-bromo-cyclohexylidenemalononitriles 8 .     

Two Syntheses of [2.2.2] (1,2,3)Cyclophane

Two syntheses are presented for [2.2.2] (1,2,3)cyclophane (7), the remaining member of the symmetrical [2_n]cyclophanes whose preparation has not previously been described. The first method involved the dimerization of 2,6-bis (4′, 4′-dimethyl-2′-oxazolinyl)toluene ( 1 ) to give 2 which, on hydrolysis, produced the tetracarboxylic acid 3 . Conversion of 3 , via the acid chloride ( 4 ), to the tetraol 5 , followed by treatment with phosphorus tribromide yielded the tetrabromide 6 . The overall scheme was then completed by reaction of 6 with phenyllithium to give [2.2.2] (1,2,3) cyclophane ( 7 ). An alternate, more convenient, method began with the pyrolysis of 2,6-bis (chloromethyl)toluene ( 8 ) to give 3-chloromethylbenzocyclobutene ( 9 ). Formation of the Grignard of 9, followed by reaction with ferric chloride, yielded the dimer 10 . Pyrolysis of 10 then gave [2.2.2] (1,2,3)cyclophane (7).     

Construction of Functionalized Azapolycyclic Architectures via Formal Amide Insertion at a Low Catalyst Loading of Copper Trifluoroacetylacetonate

A formal amide insertion reaction for the synthesis of nitrogen‐bridged polycyclic frameworks with diverse functionalities was developed using a sustainable copper catalyst as an advantageous alternative to precious rhodium catalysts. The remarkable feature of this methodology is the amount of catalyst loading (0.05 mol%). The optimized reaction conditions enable access to aromatic ring‐fused 8‐azabicyclo[3.2.1]octane, 9‐azabicyclo[3.3.1]nonane, and 6‐azabicyclo[3.2.2]nonane derivatives in moderate to excellent yields.

     

Umsetzung von (Z/E)-1-Aryl-4-arylmethylen-pyrrolidin-2,3,5-trionen mit Enaminocarbonylverbindungen

Reaction of (Z/E)-1-Aryl-4-arylmethylene-pyrrolidine-2,3,5-triones with Enaminocarbonyl Compounds Treatment of the α, β-unsaturated ketones (Z/E)- 1a–e with alicyclic or aliphatic enamines afforded cyclic Michael adducts 2 and 3a–e , respectively. By dehydration of the N,O-hemiacetals 3b–d the corresponding 1,4-dihydropyridines 4a–c were obtained. The acid-catalyzed reaction of aminosubstituted maleimides with (Z/E)- 1e , aldehydes or indan-1,2,3-trione led to 5a–c , 6a–c , 7a–c and 8 . O-Methylation of the aryl-bis(maleinimidyl)methanes 5c , 6c by using diazomethane gave 5d , 6d , whereas 5a cyclized spontaneously to the 1,4-dihydropyridine 9a . Further 1,4-dihydropyridines were prepared by cyclocondensation of 6a , b in the presence of ammonium acetate and oxidized to the pyridine derivative 10 .     

Anti-bredt monomers

Summary 1-Aza-3-oxabicyclo[3.3.1]nonan-2-one, an N-bridgehead bicyclic urethane, polymerized in bulk under the influence of dibutyltin oxide and p-toluenesulfonic acid. In solution the monomer polymerizes in the presence of phosphoric acid. This is only the second example of ring opening polymerization of a bicyclo[3.3.1]nonane. The driving force in the present case is thought to be the relief of strain energy in the monomer conferred by its chair-boat conformation.     

Group Selective Linear Polymerization of Vinyl Acrylate Using 19-Borabicyclo[3.3.1]nonane

Vinyl acrylate (VA) was polymerized with 9-borabicyclo[3.3.1]nonane (9-BBN) in tetrahydrofuran under argon at low temperatures (to -60°C). Hydroquinone and 2,6-di-tert-butyl-p-cresol had little effect on the polymerization. Addition of tetrachloromethane as a radical chain transfer agent did not lead to decrease in molecular weight of the polymer obtained. The initial rate of polymerization was proportional to [9-BBN]^0·91 and [VA]^1·37. The experimental results were indicative of non-radical properties of the propagating chain end. The polymer was soluble in organic solvents such as toluene, chloroform and N,N-dimethylformamide. The nuclear magnetic resonance measurements showed the presence of pendant vinyl groups in the polymer, indicating that only the acrylic double bond of VA reacted for polymerization to yield a linear polymer. Aniline retarded the polymerization and no polymer was formed in the presence of triethylamine. These inhibitory effects were explained on the basis of complex formation of 9-BBN with amines. This polymerization is discussed in terms of a non-radical mechanism. © of SCI.     

Synthesis,Characterization and Thermal Behaviour of 2,4,6,8‐Tetranitro‐2,4,6,8‐Tetraazabicyclo[3.3.1]Nonane‐3,7‐Dione (TNPDU) and one of its Methylene Analogues

2,4,6,8 ‐ Tetranitro – 2,4,6,8 ‐ tetraazabicyclo[3.3.1]nonane‐3,7‐dione (TNPDU) has been synthesized from propane diurea by nitration with nitric acid‐acetic anhydride with a yield of 85 %. The molecular structure of the compound has been determined by elemental analysis, IR and ¹H‐NMR spectroscopy. Some of the properties including thermal and explosion delay behaviour of the compound and its mixtures with high explosives, are reported. An analogous compound 2,5,7,9‐tetranitro‐2,5,7,9‐tetraazabicyclo[4.3.0]nonane–8–one (TNABN) has also been evaluated for some of the explosive properties considering its good stability and insensitiveness as compared to other nitrodiurea derivatives.     

Über die Synthese von Pyrimidindionen-(2,4) aus Ketonen und Harnstoff

The Synthesis of Pyrimidine-2,4-diones from Ketones and Urea By reaction of urea with 2-alkylcyclohexanones or with 2-alkylcyclohexanonecarboxamides 8-alkyl-5,6,7,8-tetrahydrobenzo-[1,2-d]pyrimidine(1H,3H)-2,4-diones ( 5a–i ) are formed. Cyclohexanone or cyclohexanone-2-carboxamide with urea form 5,6,7,8-tetrahydro-benzo-[1,2-d]pyrimidine(1H,3H)-2,4-dione ( 3 ). Menthone, 2,6-dimethylcyclohexanone, 3,5-diphenylcyclohexanone, cyclooctanone and cyclododecanone with urea yield pyrimidinediones 9, 10, 11, 12a and 12b .     

Oxidative Kupplung von 5-Amino-pyrazolen mit p-Phenylendiaminen

Oxidative Coupling of 5-Aminopyrazoles with p-Phenylenediamines By oxidative coupling of 5-amino-3-methyl-1-phenyl-pyrazole 4 with N,N-diethyl-p-phenylenediamine the 4-(4-N,N-diethylamino-phenylimino)-3-methyl-1-phenyl-2-pyrazolin-5-imin 5 is formed. 5 is oxidized very easily to the 1H-pyrazolo[3,4-b]quinoxaline 6a . The Z/E-isomerism of the azomethine dye is investigated by dynamic n.m.r.-spectroscopy. 1H-Pyrazolo[3,4-b]quinoxalines (6a–d) are also formed by reaction of 1,3-disubstituted 5-aminopyrazoles with p-nitroso-dialkylanilines.     

Isolation and structures of two divinyl ether fatty acids from <Emphasis Type="Italic">Clematis vitalba</Emphasis>

[1-14C]Linolenic acid was incubated with a homogenate of leaves of Clematis vitalba, a plant belonging to the Ranunculaceae family. Analysis of the reaction product by reversed-phase high-performance liquid radiochromatography demonstrated the presence of the following labeled oxylipins: 12-oxo-10, 15(Z)-phytodienoic acid, 9(S)-hydroxy-10(E), 12(Z), 15(Z)-octadecatrienoic acid, omega5(Z)-etherolenic acid, and 9-[1'(E), 3'(Z),6'(Z)-nonatrienyloxy]-8(Z)-nonenoic acid [8(Z)-colnelenic acid]. The last compound was a new divinyl ether FA, and an analogous compound, i.e., 9-[1'(E),3'(Z)-nonadienyloxy]-8(Z)-nonenoic acid [8(Z)-colneleic acid], was obtained following incubation of linoleic acid with the Clematis homogenate. Structures of the two divinyl ethers were assigned by spectral and chromatographic comparison with authentic compounds prepared synthetically using previously described methodology. Separate incubation of the 9- and 13-hydroperoxides of linolenic acid demonstrated that the first hydroperoxide served as the precursor of 8(Z)-colnelenic acid and indicated the presence in C. vitalba of a new divinyl ether synthase acting on 9-lipoxygenase-generated hydroperoxides. A close structural relationship between this enzyme and the well-studied divinyl ether synthase in the potato and tomato seems likely.     

二缺位Keggin型硅钨杂多酸催化的(Z,Z,Z)-3,6,9-十八碳三烯环氧化反应研究

合成了一种二缺位Keggin型硅钨杂多酸催化剂,并以此催化(Z,Z,Z)-3,6,9-十八碳三烯得到相应的单环氧化合物,并对反应溶剂,反应条件进行了优化,得到最佳反应条件为:二氯甲烷为溶剂,反应温度40℃,反应时间4~6 h,并在此基础上对反应的可能机理进行了探讨。     

Ruthenium-catalyzed reduction of allylic alcohols using glycerol as solvent and hydrogen donor

Glycerol, a biodegradable and virtually non-toxic chemical, can be used as a green solvent and hydrogen donor in the ruthenium-catalyzed reduction of allylic alcohols, a tandem process that involves the initial redox-isomerization of the allylic alcohol and subsequent transfer hydrogenation of the resulting carbonyl compound. Among the different ruthenium sources employed, the best results were obtained with the hydrophilic arene–Ru(II) complex [RuCl₂(η⁶-C₆H₆)(DAPTA)] (DAPTA = 3,7-diacetyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane), which associated with KOH generates the corresponding saturated alcohols in high yields (up to 90%) and with almost complete selectivity in short reaction times. Interestingly, these reduction processes are also operative using technical grade glycerol.     

Dienoligomerisierung. XVI. Nickelkomplexkatalysierte Codimerisierung von isomeren Octatrienen mit Ethen

Dienoligomerization. XVI. Catalytic Codimerization of Isomeric Octatrienes with Ethene by Nickel Complexes The isomeric octatrienes (n-octa-1,3c,t,7-triene 1 , n-octa-1,3c,6t-triene 2 and 3-methylhepta-1,4t,6-triene 3 ), which are easily obtained in high yields by transition metal catalysed dimerization of butadiene, react with ethene 4 in the presence of the cationic tetrakis-(triethylphosphite)-nickelhydride complex 5 to the dodimers 3-methylnona-1,4c,t,8-triene 6 , 4-vinylocta-2c, 7-diene 7 , 3-methyl nona-1,4c,t,7t-triene 8 , 4-vinylocta-2c,6t-diene 9 , 3,6-dimethylocta-1,4c,t,7-triene 10 and 3-methyl-4-vinylhepta-1,5c-diene 11 . The concentration-time dependence and a possible reaction mechanism of the codimerization are discussed and the structure data of the reaction products are reported.     

Synthesis of Poly(alcohol)s by Hydroboration/Oxidation of Poly(methylallene) Prepared by π-Allylnickel-Catalyzed Living Coordination Polymerization

Summary The π-allylnickel-catalyzed living coordination polymerization of methylallene gave polymers with predictable molecular weight and narrow molecular weight distribution in high yields. The polymers possessing various microstructural units (i.e., the ratio of the 1,2- and the 2,3-polymerizations), produced by varying the nature of the catalyst and the solvents, were subjected to the hydroboration with borane reagents such as borane tetrahydrofuran complex (BH₃•THF) and 9-borabicyclo[3.3.1]nonane (9-BBN). Subsequent oxidation gave poly(alcohol)s whose hydroxy-content could be varied by the borane reagents used. For example, the quantitative conversion of the double bonds in poly(methylallene) into the hydroxy group was attained by the hydroboration using an excess amount of BH₃•THF. Thermal properties of poly(alcohol)s were found to be dependent upon the microstructure and the hydroxy-content of the polymers.     

Zur Cyanethylierung von Hydrochinazolinonen

Cyanoethylation of Hydroquinazolinones By the reaction of acrylonitrile with octahydroquinazolinone-spirocyclohexane ( 1 ), cyanoethyl-octahydroquinazolinone-spirocyclohexane ( 2 ) is formed. Compound 2 and hydrogen-peroxide yield 5a-cyanoethyl-5-oxo-perhydro-oxaziridino[3,2-j]-quinazolin-2-spirocyclohexane ( 5 ). 2-Phenyl-octahydroquinazolinone ( 7 ) and acrylonitrile form 3,5a-biscyanoethyl-2-phenyl-octahydroquinazolinone-(4) ( 8 ). Compound 8 and hydrogenperoxide yield 3-phenyl-4,5a-biscyanoethyl-4-oxoperhydro-oxaziridino[3,2-j]-quinazoline ( 9 ). Compound 9 rearranges with ferrous sulphate to 3,4a-bis-cyanoethyl-4-oxo-8a-hydroxy-2-phenyl-octahydro-quinazoline ( 10 ).     

Polymerization of – Phenylmaleimide Initiated by 9-Borabicyclo[3.3.1]nonane

N-Phenylmaleimide (N-PMI) was polymerized by 9-borabicyclo[3.3.1] nonane (9-BBN) in tetrahydrofuran under argon at 0°C. The molecular weight distributions of the resulting polymers were around 1·1. The rate of poly-merization was proportional to [9-BBN]^1·18 and [N-PMI]^1·24. Hydroquinone had little effect on the rate of polymerization and on the molecular weight of the polymers obtained. Triethylamine completely inhibited the polymerization, and aniline with a relatively small pK_a value and zinc iodide effectively retarded the polymerization. The polymerization did not proceed either in polar dimethylformamide or in non-polar toluene. In polymerizations at temperatures higher than 60°C the conversions decreased. On the basis of the results, a non-radical mechanism was proposed for this polymerization. © of SCI.