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1.
The domino reaction of 1-aryl-1,3-bis(silyloxy)buta-1,3-dienes with 3-formylbenzopyrylium triflates, in situ generated from 3-formylchromones, afforded a variety of 2-benzoyl-4-(2-hydroxybenzoyl)phenols. 相似文献
2.
The TiCl 4-mediated [3+3] cyclization of 2,4-bis(trimethylsilyloxy)penta-1,3-diene with 3-silyloxyalk-2-en-1-ones afforded 2-acetylphenols, which were transformed into functionalized chromones. The Me 3SiOTf-mediated condensation of the latter with 1,3-bis(silyl enol ethers) and subsequent domino ‘retro-Michael-aldol-lactonization’ reaction afforded 7-hydroxy-6 H-benzo[ c]chromen-6-ones. 相似文献
3.
The Me(3)SiOTf-mediated condensation of 1-ethoxy-2-fluoro-1,3-bis(trimethylsilyloxy) 1,3-dienes with 3-cyanochromones afforded 3-cyano-2-(4-ethoxy-3-fluoro-2,4-dioxobutyl)chroman-4-ones. Their reaction with triethylamine afforded fluorinated azaxanthones or biaryls. The product distribution depends on the structure of the diene. The formation of the biaryls can be explained by an unprecedented domino "retro-Michael/aldol/fragmentation" reaction. 相似文献
4.
The reaction of 1-(3-bromopropyl)-2,5-bis(thiophen-2-yl)-1 H-pyrrole with cesium 5-methylsulfanyl-2-thioxo-1,3-dithiole-4-thiolate generated in situ gave previously unknown 4-{3-[2,5-bis(thiophen-2-yl)-1 H-pyrrol-1-yl]propylsulfanyl}-5-methylsulfanyl-1,3-dithiole-2-thione, and cross-coupling of the latter with 4,5-disubstituted 1,3-dithiole-2-thiones in the presence of triethyl phosphite afforded new substituted tetrathiafulvalenes containing a 2,5-bis(thiophen-2-yl)pyrrole fragment. Optical properties and electrochemical behavior of the synthesized compounds were studied, and their ability to undergo electropolymerization was confirmed. 相似文献
5.
Functionalized 1-azaxanthones (5-oxo-5 H-[1]-benzopyrano[2,3- b]pyridines) were prepared by TMSOTf-mediated condensation of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-cyanochromones and subsequent base-mediated domino ‘retro-Michael/nitrile-addition/heterocyclization’ reaction. 相似文献
6.
The reaction of potassium 2-(2,2-dimethylpropanoyl)-1,1,3,3-tetracyanopropenide with an equimolar amount of 2-sulfanylethanol afforded 2-{5-amino-2-( tert-butyl)-4-cyano-2-[(2-hydroxyethyl)sulfanyl]- 2,3-dihydrofuran-3-ylidene}propanedinitrile, whereas 4-amino-1-( tert-butyl)-1,6-bis[(2-hydroxyethyl)- sulfanyl]-3-imino-1,3-dihydrofuro[3,4- c]pyridine-7-carbonitrile was obtained in the reaction with excess 2-sulfanylethanol. 相似文献
7.
Bromination of 1,3-bis(aryl)-2-buten-1-ones by N-bromosuccinimide in anhydrous carbon tetrachloride gives Z-1,3-bis(aryl)-4-bromo-2-buten-1-ones.
The effect of the nature of substituent in the benzene ring on the course of a reaction with nucleophiles has been studied.
Heating an alcohol solution of these ketones (Ar = 4-MeOC 6H 4, 4-ClC 6H 4) in the presence of acid or in the presence of base (Ar = Ph) gave 2,4-bis(aryl)furans. Treatment of 1,3-bis(aryl)-4-bromo-2-buten-1-ones
with thioacetamide gave 2,4-bis(aryl)thiophenes. The oxidation of the halo-substituted dypnones with H 2O 2/NaOH gave (3-bromomethyl-3-aryl-2-oxiranyl)(aryl)methanones. The reaction of halo-substituted dypnones with aryl hydrazines
gave 1,3,5-triaryl-1,6-dihydropyridazines or 1,3,5-triarylpyridazinium bromides depending on the structure of the reagents. 相似文献
8.
The reaction of NdCl 3 with 1,3-bis(1,3-dimethyl-1 H-pyrazol-4-yl)propane-1,3-dione (HL) and 1,10-phenanthroline (Phen) in the presence of a base afforded complex [Nd(L) 3Phen] ( I). Unstable solvate I · 2CH 2Cl 2 was obtained from a solution of the complex in dichloromethane, and its structure was determined by X-ray diffraction analysis. The photophysical properties of the complex were studied. Possible routes for the energy transfer in the course of photoluminescence were proposed. 相似文献
9.
The reactions of perfluorobiacetyl with N-(4-ethoxyphenyl)- and N-methylurea afforded cis- and trans-isomers of 1-methyl-4,5-dihydroxy-4,5-bis(trifluoromethyl)imidazolidin-2-one and 1-(4-ethoxyphenyl)-4,5-dihydroxy-4,5-bis(trifluoromethyl)imidazolidin-2-one in a yield of ~60—75%. N-Alkyl(aryl)bis(trifluoromethyl)imidazooxazoles were obtained as unexpected products in the reaction of 1-alkyl(aryl)-4,5-dihydroxy-4,5-bis(trifluoromethyl)imidazolidin-2-ones with urea in dimethylacetamide. The reaction is accompanied by the rearrangement of imidazolidin-2-ones to N-alkyl(aryl)-5,5-bis(trifluoromethyl)hydantoins with CF 3 group migration from position 5 to position 4 of the starting heterocycle. A similar rearrangement is observed on boiling of the studied imidazolidin-2-ones in dimethylacetamide. The molecular structures of 3-(4-ethoxyphenyl)-5,5-bis(trifluoromethyl)imidazolidine-2,4-dione and 6-(4-ethoxyphenyl)-3a,6a-bis(trifluoromethyl)tetrahydroimidazo[4,5- d]oxazole-2,5-dione were studied by X-ray diffraction analysis. 相似文献
10.
1,4- and 1,3-C 6H 4(CH 2-9-C 2H 2B 9H 9-7,8- nido] 2 2? dianions obtained from nido-7,8-dicarbollide ion and 1,4-bis(bromomethyl)- and 1,3-bis(bromomethyl)benzenes react with (Ph 3P) 3RhCl to give binuclear rhodacarboranes, 1,4- and 1,3-[3,3-(Ph 3P) 2-3-H-3,1,2-RhC 2B 9H 10-4-CH 2] 2C 6H4. 相似文献
11.
The heating of perfluoro-3,3-diethylindan-1-one with SbF 5 at 180°C after treatment of the reaction mixture with anhydrous HF afforded perfluoro-1,3-dimethyl-4-ethylisochromen, and after hydrolysis, perfluoro-1,3-dimethyl-4-ethyl-1 H-isochromen-1-ol. The latter under the action of NaHCO 3 converted into 5,6,7,8-tetrafluoro-1,3-bis(trifluoromethyl)-1 H-isochromen-1-ol. Both isochromenols reacted with SOCl 2 gave the corresponding polyfluoro-1-chloro-1 H-isochromens. On dissolving isochromenols in CF 3SO 3H and isochromens in SbF 5 perfluoro-1,3-dimethyl-4-ethylisochromenyl and 5,6,7,8-tetrafluoro-1,3-bis(trifluoromethyl)isochromenyl cations were generated which by hydrolysis were converted into the corresponding isochromenols. 相似文献
12.
The trifluoromethyl containing heterocycles, 2-hydroxy-4-aryl-3-(thien-2-oyl)-2-(trifluoromethyl)-3,4,7,8-tetrahydro-2 H-chromen-5(6 H)-one derivatives 4, were synthesized via a one-pot three-component reaction of aldehyde 1 with 1,3-cyclohexanedione 2 and 4,4,4-trifluoro-1-(thien-2-yl)butane-1,3-dione 3 in the presence of a catalytic amount of Et 3N. The effect of bases and solvents on the reaction efficiency and yield was briefly investigated. Treatment of 4 with an excess amount of NH 4OAc in ethanol afforded 2-trifluoromethyl-1 H-quinolin-5-one derivatives 5. Refluxing of 4 with TsOH in CHCl 3 gave the corresponding dehydrated products 8. 相似文献
13.
A formal [3+3] cyclocondensation of 1,3-bis(silyl enol ethers) with the little-known 4,4-dimethylthio-1,1,1-trifluorobut-3-en-2-one was studied. In contrast to 4,4-dimethoxy-1,1,1-trifluorobut-3-en-2-one, this α-oxoketene dithioacetal reacts with 1,3-bis(trimethylsilyloxy)-1,3-butadienes in the presence of TiCl 4 to give mainly 6-methylthio-4-(trifluoromethyl)salicylates via 1,2-addition. The scope and limitations of the reaction are discussed. 相似文献
14.
The reaction of 2-(1-cyclohexen-1-yl)aniline and -6-methylaniline with phthalic anhydride has afforded 2-(2-cyclohex-1-en-1-ylphenyl)- and 2-(2-cyclohex-1-en-1-ylphenyl)-6-methylphenyl)-1H-isoindole-1,3(2H)-diones. The reaction of the obtained isoindole-1,3-diones with bromine in dichloromethane in the presence of sodium bicarbonate has led to the formation of the product of pseudo-allylic halogenation. Replacement of the halogen atom by methoxy group has been performed by keeping 2-[2-(6-bromocyclohex-1-en-1-ylphenyl)-6-methylphenyl)]-1H-isoindole-1,3(2H)-dione in a methanolic solution in the presence of NaHCO3. The reaction of 2-(2-cyclohex-1-en-1-yl-6-methylphenyl)-1H-isoindole-1,3(2H)-dione with molecular bromine in the presence of methanol has given a co-halogenation product, whereas the dibromination product has been obtained in the presence of octyl alcohol. 相似文献
15.
The 1,3-dipolar cycloaddition of 1,2-dithiole-3-thiones with alkynes to form 1,3-dithioles is one of the most studied reactions in this class of polysulfur-containing heterocycles. Nucleophilic substitution of chlorine atoms in dimethyl 2-(1,2-dichloro-2-thioxoethylidene)-1,3-dithiole-4,5-dicarboxylate, which was obtained by addition one molecules of DMAD to 4,5-dichloro-3 H-1,2-dithiole-3-thione, led to a series of 2-chloro-2-(1,3-dithiol-2-ylidene)ethanethioamides. Cycloaddition reaction of 2-chloro-2-(1,3-dithiol-2-ylidene)ethanethioamides with activated alkynes led to the unexpected formation of 2-(thiophen-3(2 H)-ylidene)-1,3-dithioles via new intermediate, 1-(1,3-dithiol-2-ylidene)- N-phenylethan-1-yliumimidothioate. Structure of dimethyl 2-(4,5-bis(methoxycarbonyl)-2-(phenylimino)thiophen-3(2 H)-ylidene)-1,3-dithiole-4,5-dicarboxylate was finally proven by single crystal X-ray diffraction study. Optimized reaction conditions and a mechanistic rationale for the 1,3-dipolar cycloaddition of novel intermediate are presented. 相似文献
16.
Reactions between the C, C′-dicopper(I) derivative of ortho-carborane and ortho-, meta- and para-diiodobenzene are reported. The reaction with 1,2-C 6H 4I 2 unexpectedly afforded 2,2′-bis(1′- ortho-carboranyl)biphenyl, [HCB 10H 10CC 6H 4] 22, whereas reactions with 1,3- or 1,4-C 6H 4I 2 provided alternative routes to 1,3-bis(1′- ortho-carboranyl)benzene 3 and 1,4-bis(1′- ortho-carboranyl)benzene 4, respectively. The crystal structure of the biphenyl derivative 2 revealed significant distortions in the biphenylene framework attributable to the proximity of the two bulky carborane cages. UV absorption spectra and electrochemical data on 2 and 3 showed little electronic communication between the two carborane cages in either, and negligible π-conjugation between the two ortho-phenylene rings in 2. However, substantial evidence was found of electronic communication between the carborane cages via the para-phenylene bridge in 4. B3LYP/6-31G ∗ computations have been carried out on compounds 2 and 4, on 4,4′-bis( ortho-carboranyl)biphenyl 6 and on 1,2-bis(1′- ortho-carboranyl)benzene 7. Those on 2, 4 and 6 show the computed geometries to be in very good agreement with the experimental geometries: those on 7 allowed the reported molecular geometry of this compound to be revised and revealed a long cage C–C bond of 1.725(3) Å. 相似文献
17.
Acylation of 6-methyl- N-[4-(pyridin-3-yl)pyrimidin-2-yl]benzene-1,3-diamine, 4-methyl- N-[4-(pyridin-3-yl)pyrimidin-2-yl]benzene-1,3-diamine, and N-[4-(pyridin-3-yl)pyrimidin-2-yl]benzene-1,3-diamine with maleopimaric and citraconopimaric acid chlorides, with benzotriazolyl maleopimarate afforded N-[3-(pyrimidin-2-yl)aryl]amides of maleopimaric and citraconopimaric acids. By the reaction of substituted N-arylamides of maleopimaric acid with methanesulfonic acid biologically active methanesulfonates were obtained. 相似文献
18.
Reactions of 1,3-bis(pyridin-2-ylmethyl)-1H-imidazol-3-ium hexafluorophosphate, ([HL1](PF 6), L1 = 1,3-bis(pyridin-2-ylmethyl)imidazolylidene) and 1,3-bis(pyridin-2-ylmethyl)-1H-benzimidazol-3-ium hexafluorophosphate ([HL2](PF 6), L2 = 1,3-bis(pyridin-2-ylmethyl)benzoimidazolylidene) with cuprous oxide in acetonitrile readily yielded trinuclear complexes [Cu 3(L1) 3(PF 6) 3] ( 1) and [Cu 3(L2) 3(PF 6) 3] ( 2). Treatment of 1 with Ni(PPh 3) 2Cl 2 and Pd(cod)Cl 2 gave [Ni(L1)Cl](PF 6) ( 3) and [Pd(L1)Cl](PF 6) ( 4), respectively, due to transmetalation. [Ni(L1) 2](PF 6) 2 ( 5) was obtained from the reaction of [Cu 3(L1) 3(PF 6) 3] and Raney nickel in acetonitrile. All these complexes have been fully characterized. Both 1 and 2 consist of a triangular Cu 3 core with each Cu–Cu bond capped by an imidazolylidene group. Each imidazolylidene acts as a bridging ligand in a μ 2 mode and is bonded equally to two Cu(I) ions. The pincer nickel and palladium complexes are square-planar and contain a tridentate NCN ligand. Complexes 3 and 4 are efficient catalyst precursors for Kumada–Corriu and Suzuki–Miyaura coupling reactions of aryl halides with organometallic reagents. 相似文献
19.
The heat-promoted reaction of 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene with cyclomanganated 2-[tricarbonyl(η 6-phenyl)chromium]pyridine afforded, upon departure of a molecule of CO, a new stable manganese alkylidene complex in which, according to X-ray diffraction analyses, the heterocyclic ligand is anti-facial with respect to the Cr(CO) 3 moiety. Similar heat-promoted reactions of unsymmetrically substituted diazoalkanes such as (Me 3Si)(H)CN 2, (Ph)(Me)CN 2, (Ph)( t-Bu)CN 2 and (Ph)(FcCH 2CH 2)CN 2, which are precursors of more electrophilic alkylidenes, with cyclomanganated 2-[tricarbonyl(η 6-phenyl)chromium]pyridine derivatives afforded new syn-facial heterobimetallic benzyl complexes. The stereoselectivity of these reactions depends on the steric demand of the substituents at the diazoalkane. A phenyl substituent at the diazoalkane favors the formation of syn-facial heterobimetallic benzyl complexes with the Ph group in the endo position. Combining this “phenyl directing effect” to the steric effect operated by a bulky group at the phenyldiazoalkane, like noticed with (Ph)( t-Bu)CN 2, led to total stereoselectivity. This study discloses four new X-ray structures of syn-facial Cr,Mn benzyl complexes, which all present the same short Cr-to-Mn distance of ca. 3.04 Å. 相似文献
20.
Reactions of 1,3-bis(pyridin-2-ylmethyl)-1H-imidazol-3-ium hexafluorophosphate, ([HL1](PF 6), L1 = 1,3-bis(pyridin-2-ylmethyl)imidazolylidene) and 1,3-bis(pyridin-2-ylmethyl)-1H-benzimidazol-3-ium hexafluorophosphate ([HL2](PF 6), L2 = 1,3-bis(pyridin-2-ylmethyl)benzoimidazolylidene) with cuprous oxide in acetonitrile readily yielded trinuclear complexes [Cu 3(L1) 3(PF 6) 3] ( 1) and [Cu 3(L2) 3(PF 6) 3] ( 2). Treatment of 1 with Ni(PPh 3) 2Cl 2 and Pd(cod)Cl 2 gave [Ni(L1)Cl](PF 6) ( 3) and [Pd(L1)Cl](PF 6) ( 4), respectively, due to transmetalation. [Ni(L1) 2](PF 6) 2 ( 5) was obtained from the reaction of [Cu 3(L1) 3(PF 6) 3] and Raney nickel in acetonitrile. All these complexes have been fully characterized. Both 1 and 2 consist of a triangular Cu 3 core with each Cu–Cu bond capped by an imidazolylidene group. Each imidazolylidene acts as a bridging ligand in a μ 2 mode and is bonded equally to two Cu(I) ions. The pincer nickel and palladium complexes are square-planar and contain a tridentate NCN ligand. Complexes 3 and 4 are efficient catalyst precursors for Kumada–Corriu and Suzuki–Miyaura coupling reactions of aryl halides with organometallic reagents. 相似文献
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