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1.
The first example of cyclic urea synthesis from secondary amines by the use of sulfur‐assisted carbonylation and oxidation was established. By combined sulfur‐assisted carbonylation of secondary α,ω‐diamines under an ambient pressure of carbon monoxide at 20°C with oxidation by molecular oxygen (0.1 MPa, 20°C), a facile synthetic method for N,N′‐dialkyl cyclic ureas including 1,3‐dimethyl‐2‐imidazolidinone was developed. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:64–68, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20508 相似文献
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T. V. Stezhko N. P. Solov'eva E. F. Kuleshova V. G. Granik 《Chemistry of Heterocyclic Compounds》1988,24(2):151-153
Depending on the conditions of carrying out the reaction of dimethylformamide diethylacetal with the Meldrum's acid, either 2,2-dimethyl-4,6-dioxo-5-(N,N-dimethyl-aminomethylene)-1,3-dioxane or N,N,N1N1-tetramethylformamidinium salt of 2,2-dimethyl-4,6-dioxo-5-(2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-yl)methylene-1,3-di-oxane are formed. The two compounds can react with primary amines to form N-substituted 2,2-dimethyl-4.,6-dioxo-5-aminomethylene-1,3-dioxanes.For Communication 51, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 184–187, February, 1988. 相似文献
4.
Busto E Gotor-Fernández V Montejo-Bernardo J Gárcía-Granda S Gotor V 《Organic letters》2007,9(21):4203-4206
The chemical synthesis and enzymatic desymmetrization of a panel of prochiral diamines have been successfully described for the first time using lipases in organic solvents. A family of 2-aryl-1,3-propanediamines has been obtained with high enantiopurity and good yields in the PSL-catalyzed reaction using diallyl carbonate in 1,4-dioxane. 相似文献
5.
A variety of 2,2-dimethyl-6-(2-oxoalkyl)-1,3-dioxin-4-ones 5a-l and the corresponding 6-substituted 4-hydroxy-2-pyrones 3a-l were prepared in high yields under mild reaction conditions by the reaction of 2,2,6-trimethyl-1,3-dioxin-4-one 4 with 1-acylbenzotriazoles 9 in the presence of LDA followed by thermal cyclization of 5a-l to 3a-l. Synthesis of novel 6-(1-benzoylalkyl)-2,2-dimethyl-1,3-dioxin-4-ones 12a-c was achieved by alkylation of dioxinone 5a and their subsequent cyclization gave 5-alkyl-4-hydroxy-2-pyrones 13a-c. 相似文献
6.
Carbonylation of functionalized diamine diols to cyclic ureas: application to derivatives of DMP 450
Synthesis of the cyclic urea core structure of the HIV protease inhibitor DMP 450 has been achieved via W(CO)6/I2-catalyzed carbonylation of diamine intermediates. Carbonylations of related functionalized diamines to derivatives of the DMP 450 core structure were also examined. Selected diamine diol substrates could be converted to the cyclic urea core structure by catalytic carbonylation without protection of the diol functionality. 相似文献
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The catalytic reduction of acetophenone, methyl α-acetamidocinnamate, and dimethyl itaconate with alcohol-modified sodium borohydride was studied in the presence of complexes CoCl2·L2 (L2 are chiral C
2-symmetric diamines: (4S,5S)-2,2-dimethyl-4,5-bis(aminomethyl)-1,3-dioxolane, (4S, 5S)-2,2-dimethyl-4,5-bis(methylaminomethyl)-1,3-dioxolane, (4S, 5S)-2,2-dimethyl-4,5-bis(dimethylaminomethyl)-1,3-dioxolane, and (4S, 5S)-2,2-dimethyl-4,5-bis(diphenylaminomethyl)-1,3-dioxolane). The maximum enantiomeric excess of (S)-1-phenylethanol was 24%, that of dimethyl α-methylsuccinate was 38%.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 342–347, February, 2005. 相似文献
9.
无外加催化剂条件下芳香醛与活性亚甲基化合物的缩合反应和迈克尔加成反应 总被引:2,自引:1,他引:2
在DMF溶剂中,不外加催化剂使芳香醛(1)与2,2-二甲基-1,3-二氧六环-4,6-二酮(2)发生缩合反应生成2,2-二甲基-5-芳亚甲基-1,3-二氧六环-4,6-二酮(3a~f)。在同样条件下,芳香醛与5,5-二甲基-1,3-环己二酮(4)则发生缩合和迈克尔加成反应生成2,2'-芳亚甲基双(3-羟基5,5-二甲基-2-环己烯-1-酮)(5a~h)。用单晶X-射线分析法确定了产物5b的晶体结构。 相似文献
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The 4,5-dihydroisoxazole-5-acetic acids 4a-j were prepared from the ketoximes 1a-j, 2,2-dimethyl-5-methoxymethylene-1,3-dioxan-4,6-dione (2) and butyllithium in yields from 35 to 79%. 相似文献
11.
Kozlov S. N. Basalaeva L. I. Ol'khovik V. K. Kalechits G. V. Matveenko Yu. V. 《Russian Journal of General Chemistry》2003,73(9):1434-1440
Bisazomethines prepared from aromatic dialdehydes and 2-naphthylamine were for the first time reacted with the following diketones: 1,3-cyclohexanedione, 5,5-dimethyl-1,3-cyclohexanedione, 5-phenyl-1,3-cyclohexanedione, indandione, and 2,2-dimethyl-1,3-dioxane-4,6-dione was studied. The reactions with 1,3-diketones of the cyclohexane series yield benzophenanthridine derivatives. The reactions with indandione, depending on conditions, give either bisarylideneindandiones or bisdihydrobenzo[f]indenoquinoline. As evidenced by the 13C NMR and IR spectra, in the case of biphenyl-4,4'-dicarbaldehyde bis[N-(2-naphthyl)imine] and 2,2-dimethyl-1,3-dioxane-4,6-dione, 4,4'-bis(3-oxo-1,2,3,4-tetrahydrobenzo[f]quinolin-1-yl)biphenyl is formed. 相似文献
12.
V. V. Shchepin Yu. G. Stepanyan P. S. Silaichev 《Russian Journal of General Chemistry》2008,78(5):929-932
Organozinc compounds prepared from dialkyl dibromomalonates and zinc react with 2-arylmethyl-eneindan-4,6-diones, 5-arylmethylene-2,2-dimethyl-1,3-dioxane-4,6-diones, as well as with 2-[4-(1,3-dioxoindan-2-ylidenemethyl)phenyl]methyleneindan-1,3-dione and 5-[4-(2,2-dimethyl-4,6-dioxo-1,3-dioxane-2-ylidenemethyl)phenyl]methylene-2,2-dimethyl-1,3-dioxane-4,6-diones to form dialkyl 3-aryl-1′3′-dioxaspiro(cyclopropane-2,2′-indan)-1,1-dicarboxylates, dimethyl 3-aryl-6,6-dimethyl-5,7-dioxa-4,8-dioxaspiro[2,5]octan-2,2-dicarboxylates, dialkyl 2-{4-[3,3-bis (alkoxycarbonyl)-1′,3′-dioxaspiro(cyclopropane-2,2′-indan)-1-yl]phenyl}-1′,3′-dioxaspiro[cyclopropane-2,2′-indan]-1,1-dicarboxylates, and dialkyl 2-{4-[2,2-bis(alkoxycarbonyl)-6,6′-dimethyl-4,8-dioxo-5,7-dioxaspiro[2,5]oct-1-yl]phenyl}-6,6-dimethyl-4,8-dioxo-5,7-dioxaspiro[2,5]octan-1,1-dicarboxylate respectively. 相似文献
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Bartolo Gabriele Raffaella Mancuso Giuseppe Ruffolo Angela Dibenedetto 《Tetrahedron letters》2009,50(52):7330-1772
In the presence of a PdI2-based catalytic system, 1,2-diols undergo an oxidative carbonylation process to afford 5-membered cyclic carbonates in good to excellent yields (84-94%) and with unprecedented catalytic efficiencies for this kind of reaction (up to ca. 190 mol of product per mol of PdI2). Under similar conditions, 6-membered cyclic carbonates are obtained for the first time through a direct catalytic oxidative carbonylation of 1,3-diols (66-74% yields). 相似文献
14.
Herbert S.-I. Chao Elizabeth Barren 《Journal of polymer science. Part A, Polymer chemistry》1993,31(7):1675-1685
Polyimides derived from 5,5′-[(2,2′,3,3′-tetrahydro-3,3,3′,3′-tetramethyl-1,1′-spirobi[1H-indene]-6,6′-diyl)bis(oxy)]bis-1,3-isobenzofurandione (spirobisindane dietheranhydride, SBIDA) and 20 plus aromatic diamines were prepared. The weight percentage of cyclic contaminants in each polyimide, estimated by gel permeation chromatography, ranges from 4 to 25%. The amount of cyclics formed in each polyimide depends on the distance and spatial orientation of the two amino groups on the aromatic diamines as well as the rigidity of the diamines. The formation of SBIDA-containing polyimide was found to be catalyzed by alkali metal ions even when the reaction was conducted in m-cresol. Thermal stability and glass transition temperature of those SBIDA-derived polyimides were examined with thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). Two promising compositions were scaled up and their mechanical properties were obtained. © 1993 John Wiley & Sons, Inc. 相似文献
15.
Summary. 5-Isopropylidene-2,2-dimethyl-1,3-dioxane-4,6-dione (the condensation product of Meldrums acid and acetone) reacts smoothly with tert-butyl isocyanide in the presence of primary or secondary amines to produce N-tert-butyl-2,2-dimethylbutyramide derivatives and/or 1-tert-butyl-4,4-dimethyl-2,5-dioxopyrrolidine-3-carboxamides in good yields. 相似文献
16.
Toyoharu Miyagawa Fumio Sanda Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2001,39(10):1629-1633
The alkali hydrolysis of poly(2,2-dimethyl-5-methylene-1,3-dioxolan-4-one) and poly(2,2-dimethyl-5-methylene-1,3-dioxolan-4-one-co-styrene) was carried out with a sodium hydroxide solution (40%) in tetrahydrofuran at room temperature to obtain poly(α-hydroxyacrylic acid) or poly(α-hydroxyacrylic acid-co-styrene) with number-average molecular weights of 39,000–73,000 in 41–86% yields. The styrene unit in the hydrolyzed copolymer hindered the formation of a lactone ring. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1629–1633, 2001 相似文献
17.
Shainyan B. A. Nindakova L. O. Ustinov M. V. Chipanina N. N. Sherstyannikova L. V. 《Russian Journal of Organic Chemistry》2002,38(12):1802-1805
The reaction of sodium diphenylamide with 2,2-dimethyl-4,5-bis(tosyloxymethyl)-1,3-dioxolane gave (+)-(4S,5S)-2,2-dimethyl-4,5-bis(diphenylaminomethyl)-1,3-dioxolane, which was brought into complex formation with cobalt chloride. Treatment of 2,2-dimethyl-4,5-bis(tosyloxymethyl)-1,3-dioxolane with sodium N-methylanilide resulted in cleavage of the SÄO bond in the p-toluenesulfonate moiety with formation of N-methyl-N-phenyl-p-toluenesulfonamide and 4,5-bis(hydroxymethyl)-2,2-dimethyl-1,3-dioxolane disodium salt. Diethyl (4R,5R)-2,2-dimethyl-1,3-dioxolane-4,5-dicarboxylate reacted with methylamine to give the corresponding dicarboxamide which was reduced with lithium aluminum hydride to (4S,5S)-2,2-dimethyl-4,5-bis(methylaminomethyl)-1,3-dioxolane having chiral carbon and nitrogen atoms. 相似文献
18.
《Tetrahedron: Asymmetry》1998,9(10):1729-1735
New chiral 1,3-dimethyl-2-iminoimidazolidines (monocyclic guanidines) were simply prepared by the action of primary amines on 2-chloro-1,3-dimethylimidazolinium chlorides, derived from the corresponding urea, in high yields. Modest asymmetric induction in alkylative esterification of benzoic acid with (1-bromoethyl)benzene was observed when the 1,3-dimethyl-4,5-diphenyl-2-[(1-phenyl- or 1-naphthyl)ethylimino]imidazolidines with all S (or R) configurations were used as bases. 相似文献
19.
The chemistry of several of the Diels-Alder adducts formed by the reaction of 4,4-diethylpyrazoline-3,5-dione ( 1 ) with conjugated dienes was studied with respect to reduction (hydride and catalytic) and reaction with base. Reaction of the 2,3-dimethyl-1,3-butadiene adduct with lithium aluminum hydride followed by hydrogenation gave 1,3,5,6,7,8-hexahydro-cis-endo-6,7-dimethyl-2,2-diethylpyrazolo[1,2-a]pyridazine ( 11 ). Attempted conversion of this compound to 3,3-diethyl-cis-7,8-dimethyl-1,5-diazacyclononane ( 12 ) gave instead a compound which has been tentatively identified as N-(2,3-dimethyl-4-aminobutyl)-2-ethyl-2-methylbutanaldimine ( 14 ). Lithium aluminum hydride reduction of 4,4-diethylpyrazolidine-3,5-dione ( 22 ) or the adducts formed from 1 and cyclopentadiene or 1,3-cyclohexadiene gave good yields of 4,4-diethylpyrazolidine ( 21 ). This later reduction gave a new and efficient synthetic route to the pyrazolidine ring system. Lithium aluminum hydride reduction of 5,6,7,8-tetrahydro-5,8-ethano-2,2-diethylpyrazolo[1,2-a]pyridazine-1,3(2H)dione ( 26 ) followed by hydrogenolysis led to a high yield of 4,4-diethyl-2,6-diazabicyclo[5.2.2]undecane ( 28 ) which is the first reported example of this ring system. Reaction of several of the adducts with ethanolic potassium hydroxide resulted in the opening of the five-membered ring. 相似文献
20.
U. B. Imashev S. M. Kalashnikov G. N. Gordeeva 《Chemistry of Heterocyclic Compounds》1983,19(4):369-373
The Lewis acid-catalyzed addition of cyclic orthoformates to vinyl ethyl ether, which leads to the formation of malonaldehyde acetals, was studied. It is shown that of the linear-cyclic malonaldehyde acetals, 2-(2,2-diethoxyethyl)- and 5,5-dimethyl-2-(2,2-diethoxyethyl)-1,3-dioxanes are stable. The transacetalization of 1,1,3,3-tetraethoxypropane with 1,2- and 1,3-diols, which leads to the formation of cyclic malonaldehyde acetals, was studied. The physicochemical constants of the acetals were determined, and their 1H and 13C NMR spectra are described.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 459–463, April, 1983. 相似文献