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1.
A simple two-step procedure for the preparation of 2-trifluoromethyl-1(substituted aryl)-4(1H)-quinolones utilizing electrophilic trifluoroacetamidoyl chlorides as the starting materials is described. The cyclization of trifluoromethyl enaminone intermediates with potassium carbonate in hot dimethylformamide produce the trifluoromethylated 4(1H)-quinolones in good to excellent yields. 相似文献
2.
Srinivas Reddy Dubbaka Shashidhar NizalapurAzmi Reddy Atthunuri Manohar SallaThresen Mathew 《Tetrahedron》2014
Synthesis of trifluoromethylated acetylenes by copper-mediated trifluoromethylation of potassium alkynyltrifluoroborates with CF3 radicals generated from NaSO2CF3 and tert-butyl hydroperoxide (TBHP) is communicated. The trifluoromethylated acetylenes were obtained in good to moderate yields. The presented method tolerates a wide range of aromatic, heteroaromatic, and aliphatic potassium alkynyltrifluoroborates. 相似文献
3.
New epoxy resins were prepared from hydroxyl substituted Schiff base monomers in two steps. The first step is based on the synthesis of hydroxyl substituted Schiff base monomers via condensation reaction. The second step includes the reaction between Schiff base monomers with epichlorohydrine (EPC) to obtain epoxy resins. The structures of resulting compounds were confirmed by FTIR and 1H-NMR. TG-DTA and DSC measurements were made for thermal characterizations of the compounds. Chemical resistances of the cured epoxy-amine systems in acidic, alkaline and organic solvents were determined for coating applications. HCl (aqueous solution, 10%), NaOH (aqueous solution, 10%), DMSO, DMF, N-methylpyrrolidone, ethanol, THF and acetone were used for corrosion tests. Chemical resistance data show that the synthesized resins have good chemical resistance against various acid, alkaline and common organic solvents. 相似文献
4.
An efficient method for the asymmetric synthesis of the trifluoromethylated propargylamines was described. Addition of lithium trifluoromethylacetylide, in situ prepared from lithium diisopropylamide and the 2-bromo-3,3,3-trifluoropropene, to various N-tert-butanesulfinyl imines provided a range of trifluoromethylated propargyl sulfinamides. Besides high yields and excellent diastereoselectivities, the additions featured that the diastereoselectivities could be reversed when polar or nonpolar solvent was used. Acidic cleavage of the tert-butanesulfinyl groups delivered highly optically pure trifluoromethylated propargylamines. 相似文献
5.
Sandrine LangleFranck David-Quillot Mohamed AbarbriAlain Duchêne 《Tetrahedron letters》2003,44(8):1647-1649
Using double Stille cross-coupling reaction bromo (or chloro)benzylbromide is easily transformed into substituted styrene monomers bearing a wide range of substituents in para position 相似文献
6.
Lorraine M. Deck Robert T. Paine Elizabeth R. BrightSabrina Ouizem Diane A. Dickie 《Tetrahedron letters》2014
Simple, aqueous-based syntheses of methylpyridine and methylpyridine N-oxide decorated 3,4-dihydro-2H-naphthoxazine and 2,3-dihydro-1H-naphthoxazine monomers, as well as thermally promoted syntheses of 3,4-dihydro-2H-benzoxazine monomers and bisoxazine methylpyridine derivatives of substituted 1,5-, 2,6-, and 2,7-dihydroxynaphthalenes are described. The crystal structures of two derivatives are presented. 相似文献
7.
Matthew Kwok Wai Choi 《Tetrahedron》2004,60(12):2903-2907
A straightforward synthesis of trityl alcohols in which one of the aryl rings is substituted with a vinyl group is presented. The synthesis of the alcohols involves the direct addition of the Grignard reagent prepared from 4-bromostyrene to substituted benzophenones. These compounds are used to incorporate trityl linker groups into polystyrene-based organic synthesis supports. Both non-cross-linked and cross-linked (JandaJel™) polystyrene have been prepared using these monomers. 相似文献
8.
Cycloaddition reactions between methyl (Z)-2-bromo-4,4,4-trifluoro-2-butenoate and various 2-tosylacetamides are described. Various 2-tosylacetamides react with methyl (Z)-2-bromo-4,4,4-trifluoro-2-butenoate in the presence of NaH at room temperature in one step to form trifluoromethylated pyroglutamates as single diastereomers. However, employing the same reactants using t-BuOK as base at ?78?°C results in the formation of trifluoromethylated 2-pyridones. A ring-closure mechanism is proposed for the reaction. 相似文献
9.
Roche AJ 《Magnetic resonance in chemistry : MRC》2004,42(11):944-949
The complete assignment of 19F, 1H and 13C NMR spectra of 11 trifluoromethylated and four bistrifluoromethylated monomers for bridge trifluoromethylated poly(p-phenylenevinylene) is described. The combination of one-dimensional 19F, 1H and 13C spectra, long-range fluorine couplings and the two-dimensional techniques of direct and long-range HETCOR (J = 140 and 8 Hz) permitted full resonance assignment. 相似文献
10.
Pteridines substituted with a 1,1‐, 1,2‐, or 1,1,3‐substituted alkenyl group (mostly (E)‐configured) at C(6) were synthesized in high yields by the intramolecular nitroso‐ene reaction of 4‐(alkenoylamino)‐2‐amino‐6‐benzyloxy‐5‐nitroso‐ and 4‐(alkenoylamino)‐2,6‐diamino‐5‐nitrosopyrimidines. Thus, the N‐alkenoyl nitrosopyrimidines 4 and 5 provided the pteridines 6 and 7 , respectively, characterized by a 1,2‐disubstituted (E)‐alkenyl substituent, the C(4)‐(E)‐geranoyl amide 13 led regio‐ and stereoselectively to the (E)‐1,1,2‐trisubstituted alkenyl‐pteridine 16 , and the C(4)‐(Z) isomer 14 led to 17 possessing a 1,1‐disubstituted alkenyl group. The trifluoromethylated butenoyl amide 15 possessing a less highly nucleophilic alkenoyl group reacted more slowly to give the trifluoromethylated vinylpteridine 18 . Also the 4‐(alkenoylamino)‐2,6‐diamino‐5‐nitrosopyrimidine 20 reacted more slowly than 4 and 5 , and provided the pteridines 23 ; introduction of additional N‐acyl groups as in 21 and 22 led to a considerably faster ene reaction. The X‐ray crystal structure analysis of the nitroso amide 15 shows eight symmetrically independent molecules in the unit cell. In the crystalline state, the N,N‐dimethylformamidine derivative 9 of 6 forms a centrosymmetric dimer with the 7,8‐lactam group connected by intermolecular hydrogen bonds. 相似文献
11.
Substituted trifluoromethylated ethenylphosphonates have been synthesized via sequential transformations of bisphosphonates in 66-92% (three steps) yields with E-isomers exclusively or predominantly. 相似文献
12.
Xingfeng Bai Caizhi Wu Shaozhong Ge Yixin Lu 《Angewandte Chemie (International ed. in English)》2020,59(7):2764-2768
An asymmetric palladium and copper co‐catalyzed Heck/Sonogashira reaction between o‐iodoacrylanilides and terminal alkynes to synthesize chiral oxindoles was developed. In particular, a wide range of CF3‐substituted o‐iodoacrylanilides reacted with terminal alkynes, affording the corresponding chiral oxindoles containing trifluoromethylated quaternary stereogenic centers in high yields with excellent enantioselectivities (94–98 % ee). This asymmetric Heck/Sonogashira reaction provides a general approach to access oxindole derivatives containing quaternary stereogenic centers including CF3‐substituted ones. 相似文献
13.
《European Polymer Journal》1985,21(6):565-568
A series of n- and iso-alkylhydroquinone and diacetate monomers was synthesized at high purity for the preparation of a series of high molecular weight aromatic polyesters of the type: poly(2-alkyl-1,4-phenylene terephthalates). The reductive alkylation of benzoquinone with the appropriate trialkylborane was selected for the synthesis of the substituted hydroquinones. 相似文献
14.
G.K.Surya Prakash Mihirbaran Mandal Chiradeep Panja Thomas Mathew George A. Olah 《Journal of fluorine chemistry》2003,123(1):61-63
A catalytic trifluoromethylation of aldehydes using trimethylamine N-oxide and trifluoromethyltrimethylsilane (TMSCF3) is described. Aromatic, aliphatic and α,β-unsaturated aldehydes provided good to excellent yields of the corresponding trifluoromethylated products. 相似文献
15.
《Arabian Journal of Chemistry》2014,7(6):1017-1023
New aromatic diamine monomers prepared from condensation reactions of aniline, p-chloroaniline, p-nitro aniline, p-chloro-m-nitro aniline with 4-amino-N,N-dimethylaniline (2:1) (aniline:reagent) in the presence of potassium dichromate in acidic media yielded new monomers of a highly colored violet and reddish-violet. Mechanism of the reaction of aniline with 4-amino-N,N-dimethylaniline in the presence of potassium dichromate as an oxidant is expected to proceed through nucleophilic substitution reaction, and the mechanism proceeds facilitated a nucleophilic attack of the substituted aniline ring on the –NH2 group of the reagent; through partial protonation of their –NH2 group, forming in diamine dye and their identification was confirmed by IR, 1H NMR, and CHN analyses. 相似文献
16.
The reactivities have been calculated for free ions involved in anionic polymerization of vinyl monomers. The copolymerization constants kAB available in the literature are compared to the stabilization energies involved in the reaction of carbanions with the same monomer. The reactivities of carbanions of living poly (2-vinyl pyridine), poly styrene and poly (substituted styrenes) with respect to 1-1,diphenylethylene have been computed. The rate constants of homopolymerisation have been compared with the variation of π energy between the “monomer” and “carbanion” states of these monomers. The occurrence of side-reactions during the polymerization of vinyl-pyridine has been investigated using quantum chemistry methods. 相似文献
17.
The reactions of arsonium bromides with (E)-α-trifluoromethylsulfonyl-α,β-unsaturated ketones in the presence of Cs2CO3 or K2CO3 proceeded smoothly under refluxing condition in dichloromethane (DCM) to give the corresponding trifluoromethylated trans-2,3-dihydrofurans in good to excellent yields with high stereoselectivity. 相似文献
18.
An efficient tandem addition/cyclization procedure for the synthesis of trifluoromethylated phthalans under mild conditions was developed. This procedure involves tetrabutylammonium fluoride (TBAF)-promoted addition of Ruppert–Prakash reagent (TMSCF3) to 2-alkynylbenzaldehyde to give 2-alkynylbenzylicalcohols, which would then undergo base-catalyzed selective 5-exo-dig cyclization to furnish the corresponding products. 相似文献
19.
Zhonglin Liu Haiwen Xiao Benxiang Zhang Haigen Shen Lin Zhu Chaozhong Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(8):2532-2535
Reported herein is an unprecedented protocol for trifluoromethylation of unactivated aliphatic C(sp3)?H bonds. With Cu(OTf)2 as the catalyst, the reaction of N‐fluoro‐substituted carboxamides (or sulfonamides) with Zn(CF3)2 complexes provides the corresponding δ‐trifluoromethylated carboxamides (or sulfonamides) in satisfactory yields under mild reaction conditions. A radical mechanism involving 1,5‐hydrogen atom transfer of N‐radicals followed by CF3‐transfer from CuII?CF3 complexes to the thus formed alkyl radicals is proposed. 相似文献
20.
Synthesis,Characterization, and Anticancer Effect of Trifluoromethylated Aurone Derivatives
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Xing Zheng Hui Wang Yun‐Mei Liu Xu Yao Min Tong Yu‐Hong Wang Duan‐Fang Liao 《Journal of heterocyclic chemistry》2015,52(1):296-301
A series of trifluoromethylated aurone derivatives were synthesized, and the structure of 6‐hydroxy‐4‐trifluoromethylated aurone was determined by single crystal X‐ray analysis. Their anticancer activities against leucocythemia (HL‐60) and colorectal adenocarcinoma (HT‐29) were evaluated by the standard MTT method in vitro with 5‐fluorouracil as a positive contrast drug. The results showed that all the (Z)‐trifluoromethylated aurone derivatives had potential anticancer activities. 相似文献