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1.
The solvent-free reaction of oligoethylene glycol diglycidyl ethers with dimercaptoethane in the presence of benzyltrimethylammonium hydroxide (Triton B) gave, via regiospecific epoxide opening reactions, dihydroxy dithiacrown ethers in excellent yields and in short reaction times.  相似文献   

2.
The reactions of enol ethers (ROCC, R = alkyl, silyl) with zinc carbenoid reagents were found to give allylic ethers in several cases along with the expected cyclopropyl ethers. The ratio of these two products was highly dependent on the concentration of the reaction mixture. Thus, the selective formation of each product was conveniently attained by merely changing the amounts of the solvent used. Zinc iodide, a by-product of the reaction, plays a key role in the present cyclopropyl to allylic rearrangement. Ring-opened ionic intermediates are proposed.  相似文献   

3.
Selective synthesis of anthracene ethers was achieved under mild conditions via an acid-catalyzed ether-ether exchange reaction and its scope and limitations, as well as its potential in synthesizing anthracene-based crown ethers, tested.  相似文献   

4.
Polymer-supported crown ethers were prepared from chloromethylated or ω-bromoalkylated polystyrene resins and hydroxymethylbenzo-18-crown-6 and 15- or 18-membered monoazacrown ethers. Effects of the cavity size of crown ethers, the degree of crosslinking, the degree of ring substitution, particle size, spacer chains, and solvents on the activity of the polymer-supported crown ethers in the reaction of 1-chloro- or 1-bromo-octane with aqueous NaI or KI were investigated and mechanisms of the reaction were discussed in terms of mass transfer, intraparticle diffusion, and intrinsic reactivity.  相似文献   

5.
Su C  Williard PG 《Organic letters》2010,12(23):5378-5381
Lithium diisopropylamide (LDA) promotes virtually quantitative conversion of allylic ethers to (Z)-propenyl ethers. It was discovered that allylic ethers can be isomerized efficiently with very high stereoselectivity to (Z)-propenyl ethers by LDA in THF at room temperature. The reaction time for the conversion increases with more sterically hindered allylic ethers. Different amides were also compared with LDA for their ability to effect this isomerization.  相似文献   

6.
Diazonium salts obtained from aminophenyl-substituted crown ethers react with paramagnetic imidazolinium salt to yield arylazoenamines, containing spin-labeled crown ethers. An alternative approach to the synthesis of related compounds, spin-labeled ureas, consists of the reaction of aminophenyl-substituted crown ethers with paramagnetic isocyanates.  相似文献   

7.
Unique structures of tetra-crown ethers were successfully synthesized by the reaction of tetramethylolmethane tetraacrylate (TMMT) reacted with crown ethers containing primary amine functional group such as 2-aminomethyl crown ethers and 4-aminobenzo crown ethers; containing secondary amine group like 1-aza crown ethers through Michael reaction. The newly synthesized tetra-crown ethers were characterized by 1H NMR, 13C NMR, FAB mass spectrum, elemental analyses, IR, respectively.  相似文献   

8.
The reaction of perfluoroalkyl vinyl ethers with electrochemically generated peroxydisulfuryl difluoride produces a mixture of α,ω-bis-fluorosulfonyloxy(perfluoroalkoxyalkanes). The fluorosulfate dimers of the starting vinyl ethers prevailing in the reaction mixture were transformed into perfluoro-2,3-dialkoxysuccinyl difluorides. High stability of intermediate radicals, in which the radical center is adjacent to the oxygen atom, is one of the factors determining the compositions of the reaction products. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1884–1889, August, 2005.  相似文献   

9.
新的酚型开链冠醚及由其衍生的二苯并冠醚的合成   总被引:2,自引:0,他引:2  
孟杰  田宝芝  黄枢 《有机化学》1996,16(3):253-257
将水杨醛与碱和氯甲基甲基醚反应, 再经过NaBH4还原, 即制得邻(甲氧基甲氧基)苯甲醇, 然后将其在DMF中与NaH和二(或三)甘醇二对甲苯磺酸酯反应, 得开链冠醚1a和1b。1a和1b经稀酸水解, 即脱保护而分别生成新的酚型开链冠醚2a和2b。用2a与二甘醇二对甲苯磺酸酯和NaH在DMF溶液中反应, 合成顺型二苯并-20-冠-6(3); 而2a与环氧氯丙烷在NaOH水溶液中反应, 则合成了17-羟基二苯并-18-冠-5(4)。  相似文献   

10.
Complexes with a 12 composition were obtained by the reaction of 8-crown-6 ethers with 4-aminobenzenesulfonamide and 4-aminobenzensulfoguanidine. Crown ethers containing a sulfanilyl group were obtained in the reaction of azacrown ethers with 4-acetylaminobenzenesulfonyl chloride.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No, 5, pp. 670–671, May 1, 1986.  相似文献   

11.
Unique structures of novel ionophores of double-armed penta-crown ethers were successfully synthesized. Diaza 18-crown-6 was designed as the parent crown ring. The penta-crown ethers were prepared by the reaction of trimethylolpropane triacrylate (TMPTA) with diaza 18-crown-6 and further with 1-aza crown ethers through the Michael reaction. The newly synthesized penta-crown ethers were characterized by 1H NMR, 13C NMR, FAB mass spectrum, IR and elemental analyses, respectively.  相似文献   

12.
Fluorinated five- to seven-membered cyclic ethers were stereoselectively synthesized from four- to six-membered cyclic ethers having an iodoalkyl substituent by fluorinative ring-expansion reaction using p-iodotoluene difluoride.  相似文献   

13.
The reaction of furfural and its homologs with vinyl and ethyl ethers of o-, m-, and p-aminophenols at room temperature without the addition of any catalyst whatever leads to the amine-aldehyde condensation with the formation of the corresponding ethers of furfurylidene-aminophenols. The structure of the latter has been shown by hydrolysis, hydrogenation, and independent synthesis.  相似文献   

14.
Heteroaryl substituted allyl and homoallyl alcohols were synthesised with two different method. Synthesis of bis-allyl ethers and homoallyl ethers were carried out via reaction of allyl bromide with allyl alcohols and homoallyl alcohols, respectively. [2.3]-Wittig Rearrangement reactions of heteroaryl substituted bis-allyl ethers were investigated using GC/MS techniques. In these reactions two unexpected products were isolated in high yield.  相似文献   

15.
Conclusions Silicoacetylenic ethers and bromoethers were synthesized by the reaction of silylethynylmagnesium bromides with-halo ethers. The bromoethers when heated with amines eliminate hydrogen bromide and are converted to the corresponding silicon-containing alkoxyenynes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2579–2580, November, 1971.  相似文献   

16.
氨基二苯醚不仅自身具有良好的杀菌、杀虫功效,广泛地应用到医药及农业领域。一般通过还原硝基二苯醚得到,但现有制备方法存在一些问题。Na2S作为一种较成熟的还原剂,价格低廉,反应后生成的Na2S2O3可作化工原料。本文用Na2S作为还原剂,合成路线如下:  相似文献   

17.
The reaction of furfural and its homologs with vinyl and ethyl ethers of o-, m-, and p-aminophenols at room temperature without the addition of any catalyst whatever leads to the amine-aldehyde condensation with the formation of the corresponding ethers of furfurylidene-aminophenols. The structure of the latter has been shown by hydrolysis, hydrogenation, and independent synthesis.  相似文献   

18.
The reactivity of allyl aryl ethers in the diene condensation with hexachlorocyclopentadiene was studied. The reactivity of aryl allyl ethers and product yield in this reaction significantly decreases when electron-withdrawing groups are introduced into the benzene ring. The reactivity is also influenced by the temperature, reaction time, and the molar ratio of the diene and dienophile.  相似文献   

19.
Unsolvated methyl cations, generated by spontaneous -decay of multitritiated methane, have been allowed to react with some aliphatic ethers. The reaction mixtures contain various products, mainly aliphatic ethers, that have been separated by gaschromatography and continuously counted in an ionization chamber. A mechanism involving different reaction channels can provide an explanation of the results.  相似文献   

20.
The Wittig rearrangement of fluorenyl ethers by the use of potassium hydroxide as base in solid phase was readily effected by crown ethers and onium salts, while diamines moderately catalyzed the reaction.  相似文献   

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