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1.
Three new bis-triazolinediones, 3,3′-dimethyl-4,4′-bis-[3,5-dioxo-1,2,4-triazoline-4-yl]biphenyl, t-1,4-bis-[3,5-dioxo-1,2,4-triazoline-4-yl]methyl cyclohexane, and 4,4′-bis-[3,5-dioxo-1,2,4-triazoline-4-yl] phenyl ether, were synthesized from their corresponding bis-amines or bis-isocyanates. The compounds were identified by their quantitative ene reaction with 2,3-dimethyl-2-butene. The high degree of reactivity of the triazoline moiety makes solvent selection for reaction media rather difficult. This fact prompted a study of rates of reaction with a variety of polar and nonpolar solvents, including halogenated aliphatics, aromatics, tetrahydrofuran (THF), and N,N-dimethylformamide (DMF). The compounds exhibited reasonable stability in the halogenated solvents, as well as in the aliphatic and aromatic hydrocarbons, but they underwent reaction with THF and DMF. The structure of the reaction product of N-phenyl-1,2,4-triazoline-3,5-dione in DMF solution was determined, and a mechanism for product formation was proposed. Two of the bis- triazolinediones were polymerized via a base-catalyzed condensation mechanism which eliminates N2 from the triazolinedione ring. 相似文献
2.
[reaction: see text] Photooxygenation of the chiral allylic alcohol 4-methyl-3-penten-2-ol (3) in nonpolar solvents and subsequent Lewis acid-catalyzed peroxyacetalization afforded a series of monocyclic and spirobicyclic 1,2,4-trioxanes (5, 6). Two products show significant anti-Malaria activity against Plasmodium falciparum when compared with chloroquine. 相似文献
3.
O'Neill PM Mukhtar A Ward SA Bickley JF Davies J Bachi MD Stocks PA 《Organic letters》2004,6(18):3035-3038
[reaction: see text] Thiol-olefin co-oxygenation (TOCO) of substituted allylic alcohols generates alpha-hydroxyperoxides that can be condensed in situ with various ketones to afford a series of functionalized 1,2,4-trioxanes in good yields. Manipulation of the phenylsulfenyl group in 4a allows for convenient modification to the spiro-trioxane substituents, and we describe, for the first time, the preparation of a new class of antimalarial prodrug. 相似文献
4.
A recently published paper1 reporting a new synthetic route to the ethylene glycol mono-ketal of cyclohexane-1,4-dione promted us to publish the results obtained in our laboratory. In fact we have developed a different synthesis of (2), starting from cyclohexane-1,4-diol (1), with overall yields higher than those reported in the above mentioned paper and without employment of any anhydrous solvent. 相似文献
5.
The synthesis of a series of eight β-naphthyl-substituted 1,2,4-trioxanes 3a-h by a sequence of singlet oxygen ene reaction of allylic alcohols 1a-h and Lewis acid catalyzed peroxyacetalization of the allylic hydroperoxides 2a-h with β-naphthaldehyde is reported. The ene reactions were performed by solid-state photooxygenation in dye-crosslinked polystyrene beads and resulted in mixtures of diastereoisomeric hydroperoxides 2. Boron trifluoride catalyzed peroxyacetalization resulted in the formation of 3, as well as the 1,2,4-trioxanes 4 and 5, which were formed via acid catalyzed β-hydroperoxy alcohol cleavage. 相似文献
6.
CHEN Jiao SHI Jian YAN Chao-guo College of Chemistry & Chemical Engineering Yangzhou University Yangzhou P. R. China 《高等学校化学研究》2011,27(1):49-53
The 1,4-diazabicyclo[2.2.2]octane(DABCO) catalyzed reaction of cyclohexane-1,3-dione or dimedone with various aldehydes in acetonitrile resulted in the polysubstituted tetraketones, spiro dihydrofurans or 1,8-dioxo-xanthenes derivatives as main products respectively according to the structure of reactants and reaction conditions. 相似文献
7.
Wolf-Diethard Pfeiffer Anja Bodtke Jana Mücke Annemarie Hetzheim Pavel Pazdera 《Journal of heterocyclic chemistry》1999,36(5):1327-1336
The preparation of 1,2,4-triazolo[1,5-c]quinazolines 4a-d , 5 , 8a-d by cyclocondensation of 1a-c with carboxylic acids and carboxylic anhydrides, respectively, is described. By different pathways, the 5-thioxo-5,6-dihydro-1,2,4-triazolo[1,5-c]quinazolines 4a-d react with hydrazine hydrate or amines with the formation of 5-substituted 1,2,4-triazolo[1,5-c]quinazolines 9 and 10a-d . Cyclocondensation of 9 with carboxylic acids, carboxylic anhydrides, and nitrous acid, respectively, leads to the new anellated heterocycles bis-1,2,4-triazolo[4,3-a:1,5-c]quinazoline 13 and tetrazolo [1,5-a]-1,2,4-triazolo[1,5-c]quinazoline ( 14 ). 相似文献
8.
N. G. Kozlov E. A. Dikusar B. A. Odnoburtsev 《Russian Journal of Organic Chemistry》2008,44(10):1504-1507
Reactions of succinyl chloride with 4-hydroxy-3-methoxybenzaldehyde and 3-ethoxy-4-hydroxybenzaldehyde gave the corresponding succinates which were brought into the condensation with naphthalen-2-amine to obtain Schiff bases. The latter reacted with CH acids (cyclohexane-1,3-dione and 5,5-dimethylcyclohexane-1,3-dione) to form bis[2-alkoxy-4-(11-oxo-7,8,9,10,11,12-hexahydrobenzo[a]acridin-12-yl)phenyl]-succinates which can also be obtained by three-component heterocyclization of naphthalen-2-amine with bis-(2-alkoxy-4-formylphenyl)succinates and CH acid. 相似文献
9.
The adducts of cyclohexane-1,4-dione with HgCl2, ZnCl2, and TiCl4 have been prepared, and the IR. absorption spectra of the solid products studied. The lowering of the carbonyl frequency shows that the acceptor is linked by dative bonds to the carbonyl oxygen donors. This result confirms the cyclohexane-1,4-dione · HgCl2 structure which has been determined by X rays diffraction. 相似文献
10.
Martín J. Riveira 《Tetrahedron letters》2010,51(5):804-169
Heterogeneous catalytic hydrogenation of unsaturated 1,2,4-trioxanes derived from β-ionone-type dienones has been investigated. Our studies revealed a versatile reactivity of trioxanic substrates that led to the development of reaction methodology for the selective manipulation of the alkene and peroxide functionalities. Depending on the catalytic system used, divergent reaction pathways can be controlled to afford either the corresponding saturated 1,2,4-trioxanes or furan structures. A mechanistic rationalisation, which accounts for the reductive behaviour of these heterocycles, is proposed. 相似文献
11.
Mariza N. AlbertiGeorgios C. Vougioukalakis Michael Orfanopoulos 《Tetrahedron letters》2003,44(5):903-905
The regioselectivity of the ene pathway in the photooxidation of several 1-aryl-2-methylpropenes, as probed by stereoselective deuterium-labeling, depends on the electronic nature of the para phenyl-substituents. The reaction of the same array of alkenylarenes with 4-methyl-1,2,4-triazoline-3,5-dione (MTAD) gives ene products with an impressive >97% allylic hydrogen abstraction from the more substituted side of the alkene. 相似文献
12.
Several derivatives of mesoionic imidazo[1,2-α]pyrimidine-5,7-dione and 1,2,4-triazolo[1,5-α]pyrimidine-5,7-dione, two new examples of mesoionic xanthine ring systems, were prepared and characterized. These compounds were conveniently prepared by the condensation of bis-(2,4,6-trichlorophenyl) malonates with the appropriately substituted alkylaminoimiazole or 1,2,4-triazole. 相似文献
13.
E. V. Rudyakova D. O. Samul’tsev G. V. Bozhenkov G. G. Levkovskaya 《Russian Journal of Organic Chemistry》2011,47(12):1870-1873
First representatives of bis-2-chloro- and 2,2-dichlorovinyl ketones, 1,10-dichlorodeca-1,9-diene-3,8-dione and 1,1,10,10-tetrachlorodeca-1,9-diene-3,8-dione,
were synthesized by reaction of hexanedioyl dichloride with acetylene and 1,1-dichloroethene, respectively, in the presence
of AlCl3. 1,1,10,10-Tetrachlorodeca-1,9-diene-3,8-dione reacted with benzylhydrazine and 1,1-dimethylhydrazine to give 1,4-bis(1-benzyl-5-chloro-1H-pyrazol-3-yl)butane and 1,4-bis(5-chloro-1-methyl-1H-pyrazol-3-yl)butane, respectively. 相似文献
14.
Singh C Pandey S Saxena G Srivastava N Sharma M 《The Journal of organic chemistry》2006,71(24):9057-9061
Homoallylic alcohols 4a-d, easily accessible in two steps from cyclopropyl methyl ketone, underwent a highly regioselective reaction with singlet oxygen to yield gamma-hydroxyhydroperoxides 5a-d in 57-72% yield. Acid-catalyzed reaction of 5a-d with acetone, cyclopentanone, and cyclohexanone furnished 1,2,4-trioxepanes 8a-d, 9a-d, and 10a-d in good yields. Homoallylic alcohol 12 also underwent a highly regioselective photooxygenation to yield gamma-hydroxyhydroperoxide 13 in 67% yield, which on reaction with acetone, cyclopentanone, and cyclohexanone, furnished 1,2,4-trioxocanes 16-18 in 41-55% yield. 相似文献
15.
Kevin L. Brown Lorenz Damm Jack D. Dunitz Albert Eschenmoser Reinhard Hobi Christoph Kratky 《Helvetica chimica acta》1978,61(8):3108-3135
Crystal structure analyses of five crystalline enamines together with recently published structural data for two other enamines reveal varying degree of pyramidality at the enamine nitrogen atom. The pyramidality appears to be most pronounced in enamines from piperidine and morpholine, less so in enamines derived from prolinoid amines. A pyrolidine enamine obtained from a derivative of cyclohexane-1,4-dione seems to have a virtually planar enamine group. The implications of these findings for current stereochemical problems in enamine chemistry are discussed. 相似文献
16.
Sixteen 3-aryl-4-oxo-2-phenyl-4,5,6,7-tetrahydroindazoles were obtained from the reaction of the phenylhydrazones of dimedone
and cyclohexane-1,3-dione with 3-bromo-, 4-bromo-, 4-chloro-, 4-fluoro-, 2-hydroxy-, 4-hydroxy-, 4-methoxy-, 2-nitro-, 3-nitro-,
4-nitro-, and 4-dimethylamino-benzaldehydes. The interaction of the tosylhydrazones of dimedone and cyclohexane-1,3-dione
with the substituted benzaldehydes gave thirteen 3-aryl-4-oxo-4,5,6,7-tetrahydroindazoles.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1662–1668, November 2005. 相似文献
17.
Jia-Yan Liu Jin-Xing Xu Xiao-Ming Qiao Ya Cai Dong-Sheng Chen 《Journal of heterocyclic chemistry》2020,57(11):3890-3897
A new series of pyrazino[2,3-a]acridine derivatives were prepared, via three-component reaction of quinoxalin-6-amine, aromatic aldehydes and 5,5-dimethyl cyclohexane-1,3-dione or cyclohexane-1,3-dione in ethanol as a solvent at reflux. The advantages of this protocol include mild reaction conditions, easy purification, high yields, and catalyst-free approach. 相似文献
18.
Bicyclo[3.2.1]octan-8-ones have been prepared from a tandem Michael-Henry reaction between cyclohexane-1,2-diones and nitroalkenes using a quinine-derived thiourea as the catalyst. Although four stereogenic centers were created during the reaction, only two diastereomers were obtained in good diastereoselectivity and high enantioselectivity (92-99% ee). When 3-methylcyclohexane-1,2-dione (R1=Me) was used as the substrate, only the regioisomeric product of the corresponding thermodynamic enolate was obtained. 相似文献
19.
A route for the synthesis of bicyclo[3.1.0]hexane-derived conformationally restricted analogues of beta-arabinofuranosyl and alpha-galactofuranosyl rings is described. Advantage is taken of the pseudo-enantiomeric relationship between the two ring systems to develop a route that provides both targets from a single precursor. Key steps include a base-promoted ring contraction of an epoxy ketone obtained from cyclohexane-1,4-dione to give the bicyclo[3.1.0]hexane ring system and a late stage resolution involving esterification with O-acetyl-(S)-mandelic acid. 相似文献
20.
Neumann MA 《The journal of physical chemistry. B》2008,112(32):9810-9829
A general procedure is presented to derive a complete set of force-field parameters for flexible molecules in the crystalline state on a case-by-case basis. The force-field parameters are fitted to the electrostatic potential as well as to accurate energies and forces generated by means of a hybrid method that combines solid-state density functional theory (DFT) calculations with an empirical van der Waals correction. All DFT calculations are carried out with the VASP program. The mathematical structure of the force field, the generation of reference data, the choice of the figure of merit, the optimization algorithm, and the parameter-refinement strategy are discussed in detail. The approach is applied to cyclohexane-1,4-dione, a small flexible ring. The tailor-made force field obtained for cyclohexane-1,4-dione is used to search for low-energy crystal packings in all 230 space groups with one molecule per asymmetric unit, and the most stable crystal structures are reoptimized in a second step with the hybrid method. The experimental crystal structure is found as the most stable predicted crystal structure both with the tailor-made force field and the hybrid method. The same methodology has also been applied successfully to the four compounds of the fourth CCDC blind test on crystal-structure prediction. For the five aforementioned compounds, the root-mean-square deviations between lattice energies calculated with the tailor-made force fields and the hybrid method range from 0.024 to 0.053 kcal/mol per atom around an average value of 0.034 kcal/mol per atom. 相似文献