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1
Content available Mild Method to Synthesize TATB by Amination of 1,3,5-Trialkoxy-2,4,6-Trinitrobenzene under Phase Transfer Catalysis Conditions
Chang T., Li B., Chen L., Ge L., Lu M.
Central European Journal of Energetic Materials
|
2017
|
Vol. 14, no. 1
47--59
EN
Nucleophilic amination, as a vital step in the synthesis of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) using 1,3,5-trialkoxy-2,4,6-trinitrobenzene (TORTNB) and aqueous ammonia as the starting materials and catalyzed by phase transfer catalysis (PTCs) under mild conditions is described. Various phase transfer catalysts, such as crown ethers, tertiary amines, quaternary ammonium salts, poly ethers and cyclodextrin, and various experimental parameters, such as no. of equivalents of PTC, mole ratio of ammonium hydroxide to the starting material, reaction time, reaction temperature and cycle times of the organic phase were investigated. The crown ethers, especially 18-crown-6, show good catalytic activity and re-usability for the amination of 1,3,5-triethoxy-2,4,6-trinitrobenzene giving a yield of 96.52%. This makes for a safe process and suitable for scale-up, because the reactions are carried out under atmospheric conditions. The material synthesised by the new system was characterized by DSC, SEM and LPS.
2
Content available Efficiency of selected phase transfer catalysts for the synthesis of 1,2-epoxy-5,9-cyclododecadiene in the presence of H2O2/H3PW12O40 as catalytic system
Lewandowski G.
Polish Journal of Chemical Technology
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2013
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Vol. 15, nr 3
96-99
EN
The results of the studies on the influence of the phase transfer catalyst on the epoxidation of (Z,E,E)-1,5,9-cyclododecatriene (CDT) to 1,2-epoxy-5,9-cyclododecadiene (ECDD) in the H2O2/H3PW12O40 system by a method of phase transfer catalysis (PTC) were presented. The following quaternary ammonium salts were used as phase transfer catalysts: methyltributylammonium chloride, (cetyl)pyridinium bromide, methyltrioctylammonium chloride, (cetyl)pyridinium chloride, dimethyl[dioctadecyl(76%)+dihexadecyl(24%)] ammonium chloride, tetrabutylammonium hydrogensulfate, didodecyldimethylammonium bromide and methyltrioctylammonium bromide. Their catalytic activity was evaluated on the basis of the degree of CDT and hydrogen peroxide conversion and the selectivities of transformation to ECDD in relation to consumed CDT and hydrogen peroxide. The most effective PT catalysts were selected based on the obtained results. Among the onium salts under study, the epoxidation of CDT with hydrogen peroxide proceeds the most effectively in the presence of methyltrioctylammonium chloride (Aliquat® 336) and (cetyl)pyridinium chloride (CPC). The relatively good results of CDT epoxidation were also achieved in the presence of Arquad® 2HT and (cetyl)pyridinium bromide.
3
Content available remote Złoty jubileusz katalizy międzyfazowej
Fedoryński M.
Przemysł Chemiczny
|
2010
|
T. 89, nr 11
1428-1435
4
Content available remote Nowe aspekty alkilowania aryloacetonitryli w warunkach katalizy międzyfazowej
Fedoryński M., Jezierska-Zięba M., Kąkol B.
Przemysł Chemiczny
|
2009
|
T. 88, nr 8
872-876
5
Content available remote Zastosowanie reaktora helikoidalnego do prowadzenia procesu polikondensacji na granicy rozdziału faz
Woliński J., Wroński S.
Czasopismo Techniczne. Mechanika
|
2008
|
R. 105, z. 2-M
385-400
PL
W celu intensyfikacji procesu polikondensacji bisfenolu A z chlorkami kwasów ftalowych w warunkach przeniesienia międzyfazowego zastosowano reaktor helikoidalny. Zaprezentowano wpływ stosunku molowego monomerów, natężenia przepływu mieszaniny i rozmiaru szczeliny na właściwości produktu (średni ciężar cząsteczkowy MW i stopień polidyspersji PI). Wykazano możliwość uzyskania produktu nadającego się do zastosowań optycznych. Pożądane właściwości produktu otrzymano dla następujących zakresów parametrów procesowych: 0,7
EN
The helicoidal reactor was applied in the aim of the intensification interfacial polycondensation process. The influence of the molar ratio of monomers, mixture flow rate and annular gap size on properties of the product (average molecular weight MW and polydispersity index PI) was presented. The possibility of the obtainment of the product being suitable to optical applications was showed. The desirable proprieties of the product were received for the following ranges of the process parameters: 0,7 < M0 < 0,9 and 1300 [is less than or equal to] Rerot [is less than or equal to] 1550 for T = 20[degrees]C, [tau]=60s and [eta]=0,93. It was got considerably shorter residence times in the comparison to the tank reactor.
6
Content available Comparison of the methods of the phase transfer catalysis and hydroperoxide in the epoxidation of 1,5,9-cyclododecatriene
Lewandowski G.
Polish Journal of Chemical Technology
|
2007
|
Vol. 9, nr 3
101-104
EN
The process of the epoxidation of cis,trans,trans- 1,5,9-cyclododecatriene (CDT) to 1.2-epoxy-5,9-cyclododecadiene (ECDD) with the 30% aqueous hydrogen peroxide under the phase transfer conditions and with /tert-butyl hydroperoxide under the homogeneous conditions was investigated. Onium salts such as AliquatŽ 336, ArquadŽ 2HT, methyltrioctylammonium bromide and the Na2WO4/H3PO4 catalyst system are very active under the phase transfer catalysis (PTC) conditions for the selective epoxidation of cis,trans,trans-1,5,9-cyclododecatiene (PTC method). These catalytic systems were found to be as active and selective as the homogeneous phase system Mo(CO)6/TBHP (hydroperoxide method).
7
Content available remote Epoxidation of allyl ethers under PTC conditions. Model epoxidation of 1,4-bis(allyloxy) butane
Kaczmarczyk E., Janus E., Milchert E.
Polish Journal of Chemical Technology
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2006
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Vol. 8, nr 2
20-21
EN
The epoxidation of 1,4-bis(allyloxy)butane as a model for allyl ethers with 30 wt% hydrogen peroxide under two phase conditions with an onium salt as the phase transfer catalyst was studied. The reaction led to two epoxides, monoepoxide (1-allyloxy-4-glycidyloxybutane (1)) and diepoxide (1,4-bis(glycidyloxy)butane (2)). The influence of the type of the phase transfer catalyst -onium salt- was studied.
8
New Routes to Functionalized Polyhedral Oligomeric Silsesquioxanes via Friedel-Crafts Alkylation and Dichlorocarbene Addition to Octavinylsilsesquioxane
Dare E., Olatunji G., Ogunniyi D., Lasisi A.
Polish Journal of Chemistry
|
2005
|
Vol. 79 / nr 1
109-114
EN
Selective functionalization of (CH2=CH)8Si8O12 1 by the addition of dichlorocarbene to vinyl double bonds giving (C3H3)8Si8O12 2 or (C2H3)4(C3H3Cl2)4Si8O12 3 respectively is described. The dichlorocarbene was generated from CHCl3 in phase transfer catalytic system (PTC). Furthermore, (PhCH2CH2)8Si8O12 4 has been synthesized by Friedel-Crafts alkylation reaction of benzene with 1 using AlCl3 as catalyst.
9
Mild Conditions Synthesis of Mixed Organic Peroxides from Alkyl Halides and Organic Hydroperoxides
Baj S., Krawczyk T., Siewniak A., Rączkowska A.
Polish Journal of Chemistry
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2004
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Vol. 78 / nr 3
381-384
EN
The synthesis of mixed organic peroxides by reaction of alkyl halides with tertiary hydroperoxides under basic phase-transfer catalysis conditions was described.
10
Content available remote Recycling of the catalyst in the etherification process of polyhydric alcohols using a PTC technique
Janus E.
Polish Journal of Chemical Technology
|
2004
|
Vol. 6, nr 3
16-20
EN
The conditions of recycling the PT catalyst (tetrabutylammonium salt) for the etherification process of 1,4-butanediol with allyl chloride, carried out in the presence of sodium hydroxide aqueous solution and toluene as a non-polar solvent were investigated. The distribution of the catalyst among the phases and the conditions of the formation of the third liquid phase by changing the composition of the organic and the aqueous phase were searched. Important compounds and their amounts have been established by the etherification process conditions. The effects of base (NaOH), salt (NaCl), 1,4-butanediol, the catalyst concentration and the composition of the organic phase, including toluene, allyl chloride, etherification products (1,4-diallyloxybutane and 4-allyloxybutan-l-ol) on the formation of the third liquid phase were investigated. These results allowed producing the scheme of 1,4-diallyloxybutane synthesis with the recycling of the catalyst.
11
Phase Transfer Catalyzed Reactions of Chloroform with Methacrylic Esters
Fedoryński M., Błażejczyk A., Mąkosza M.
Polish Journal of Chemistry
|
2003
|
Vol. 77 / nr 5
709-717
EN
Chloroform reacts with an excess of methyl methacrylate in the presence of 50% aq NaOH and benzyltriethylammonium chloride (TEBA) as a catalyst (phase transfer catalysis, PTC) to give a mixture of dichlorocarbene and trichloromethyl anion adducts, 1 and 2, respectively. These additions proceed as parallel processes, there is a slow conversion of 2_ 1, which proceeds as an intramolecular process.
12
Dimerization of Phenylindenes by Means of Perchloroalkanes Under Conditions of Phase Transfer Catalysis
Jończyk A., Szymanek P., Juszczuk C.
Polish Journal of Chemistry
|
2000
|
Vol. 74, nr 7
985-988
EN
Penyl substitued indenes 1 react with tetrachloromethane or hexachloroethane HCE in the presence of 50% aq. KOH and benxyltriethylammonium chloride as a catalyst to give dimmers in 23-48% yield.
13
Allylation of Sugar Diols Under Phase Transfer Conditions Using Potassium Carbonate as a Base
Jarosz S., Szewczyk K.
Polish Journal of Chemistry
|
2000
|
Vol. 74, nr 8
1115-1122
EN
Allylation of sugar vic-diols (with a primary and secondary OH groups) under the phase transfer conditions (allyl bromide, K2CO3, 18-crown-6, toluene) afforded a mixture of both monosubstituted allyl ethers and small amounts of the di-allyl derivative. Interestingly, the cyclic carbonate was also isolated from the post reaction mixture. Its formation may be explained by reaction of the di-allyl carbonate, formed in situ under the reaction conditions, with the 1,2-diol.
14
The Synthesis of Organic peresters via the Phase Transfer Catalysis
Baj S., Chrobok A.
Polish Journal of Chemistry
|
1999
|
vol. 73 nr 7
1185-1189
EN
The acylation of alkyl hydroperoxydes with acid chlorides under the phase transfer conditions (PTC) is studied. An evident catalytic effect was observed. This reaction can be considered as a convenient method for the synthesis of organic peresters.
15
Synthesis of O,O,O-Triaryl Phosphorothioates and O-Aryl Phosphorodichloridothioates Using Poly(ethylene glycol) as a Phase Transfer Catalyst
Jadhav V., Wadgaonkar P., Salunkhe M.
Polish Journal of Chemistry
|
1999
|
Vol. 73, nr 9
1473-1475
EN
O,O,O-Triaryl phosphorothioates and O-aryl phosphorodichloridothioates have been prepared in good yields and purity from thiophosphoryl chloride and phenol using poly(ethylene glycol)-400 (PEG-400) as a phase transfer catalyst.
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