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1.
Boron trifluoride reacted with dipyrid-2-ylamine 6 , its N-methyl and 6,6′-dimethyl derivatives 8 and 10 , and 3,3′,5,5′-tetraphenyl-6-azapyrromethene 13 to give fluorescent β-azavinamidine (1,3,5-triazapenta-1,3-diene) dyes: 10-azapyridomethene–BF2 complex 5 (λf 422 nm, λlas 426 nm), its quaternary 10-methyl tetrafluoroborate and 4,6-dimethyl derivatives 9 (λf 362 nm) and 11 (λf 416 nm), and 1,3,5,7-tetraphenyl-8-azapyrromethene–BF2 complex 17 (λf 696 nm). Treating 3,3′,4,4′-tetraphenyl-5,5′,6-trimethylpyrromethene (prepared in situ from ethyl 3,4-diphenyl-5-methylpyrrole-2-carboxylate in a reaction with acetyl chloride) with boron trifluoride gave 1,2,6,7-tetraphenyl-3,5,8-trimethylpyrromethene–BF2 complex 21 . Absorption for the vinamidine chromophore differed from that for the β-azavinamidine chromophore by a hypsochromic shift of 86 nm in a comparison of pyridomethene–BF2 complex 3 with its 10-aza derivative 5 and by a bathochromic shift of 105 nm in a comparison of the pyrromethene–BF2 complex 20 with the 8-azapyrromethene–BF2 complex 17 .  相似文献   

2.
The homoleptic complexes of Zn(II) with 3,3′,5,5‘-tetraphenyl-2,2’-dipyrrolylmethene and 3,3′,5,5′-tetraphenyl-ms-aza-2,2′-dipyrrolylmethene [ZnL2] have been prepared, and their spectral and luminescent properties have been studied. The complex with 3,3′,5,5′-tetraphenyl-2,2′-dipyrrolylmethene exhibited an intense fluorescence in the nonpolar medium, efficiently quenched in the polar solvents; thus, it can be used as a fluorescent sensor of the medium polarity.  相似文献   

3.
The naturally occurring polybrominated indoles 2,2′,5,5′-tetrabromo-3,3′-bi-1H-indole, 2,2′,6,6′-tetrabromo-3,3′-bi-1H-indole, and 2,2′,5,5′,6,6′-hexabromo-3,3′-bi-1H-indole were synthesized using a palladium catalyzed, carbon monoxide mediated, double reductive N-heterocyclization of 2,3-bis(2-nitro-4(or 5)-bromophenyl)-1,4-butadienes as the key step.  相似文献   

4.
Reactions of salicylaldehyde, 3-tert-butylsalicylaldehyde, and 3,5-di-tert-butylsalicylaldehyde with 1,4-diaminobutane, 1,6-diaminohexane, 4,4′-diaminodiphenylmethane, 4,4′-diamino-3,3′,5,5′-tetramethyldiphenylmethane, 4,4′-diamino-5,5′-dicyclopentyl-3,3′-dimethyldiphenylmethane, 4,4′-diamino-5,5′-dicyclohexyl-3,3′-dimethyldiphenylmethane, bis(4-aminophenyl) sulfone, o,o′- and p,p′-diaminodiphenyl ethers, 1,4-bis(4-aminophenoxy)benzene, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, and 4,4″-diamino-p-terphenyl gave a series of the corresponding Schiff bases which can be used as tetradentate ligands for the synthesis of titanium and zirconium complexes.  相似文献   

5.
N. Ishibe  M. Sunami  M. Odani 《Tetrahedron》1973,29(14):2005-2008
Photolysis of 2,6-diphenyl-4H-pyran-4-thione and 2,6-diphenyl-4H-thiopyran-4-thione resulted in desulfurization and furnished 2,2′,6,6′-tetraphenyl-4,4′-di(pyranylidene) and 2,2′,6,6′-tetraphenyl-4,4′-di(thiopyranylidene) as the products. The mechanism was studied by quantum yield measurements. In dioxane, the quantum yield of di(pyranylidene) formation was concentration-dependent, while in benzene, it was independent of the concentration. The photoreaction proceeds via the triplet state of 2,6-diphenyl-4H-pyran-4-thione and 2,6-diphenyl-4H-thiopyran-4-thione and the H atom abstraction from solvents appears to be a key step in the formation ofdi(pyranylidene).  相似文献   

6.
《Tetrahedron: Asymmetry》2003,14(2):245-253
2,2′,5,5′-Tetracarboxy- and 2,2′,5,5′-tetracarbamoyl-substituted biphenyls and also the 2,2′,3,3′,6,6′-hexacarboxy-substituted analogue behave as Siamese twins of terephthalic tectons in the single crystal self-assembly, giving rise to chiral 2D grid layers. A comparison has been made with the corresponding 2,2′,6,6′-tetrasubstituted biphenyls which mimic isophthalic twins in their self-assembly.  相似文献   

7.
2-Chloro-3,4,5-tris(trifluoromethylthio)pyrrole ( 2a ), 3-Chloro-2,4,5-tris(trifluoromethylthio)pyarrole ( 2b ) and 3,4-dichloro-2,5-bis(trifluromoethylthio)pyrrole ( 2c ) react with silver nitrate/silver acetate in good yield to give the corresponding N-silver salts 3a-c . Compound 2b forms with an aqueous potassium hydroxide solution the N-potassium salt 4 . Compounds 3a and 3b react with iodine to give the dimeers 2,2′-dichloro-3,3,′ 4,4′5,5′-hexakis(trifluoromethylthio)-2,2′-bi-2H-pyrrolyl ( 5a ) and 3,3′-dichloro-2,2′,4,4′,5,5′-hexakis(trifluoromethylthio)-2,2′-bi-2H-pyrrolyl ( 5b ). The dimers dissociate in solution to the corresponding pyrrolayl radicals. The esr and endor spectra of 3-chloro-2,4,5-tris(trifluoromethylthio)pyrrolyl were measured; coupling constants are given. For the newly prepared substances melting-points, 19F-nmr and ir spectroscopical data are provided.  相似文献   

8.
Effect of complexing atom, molecular structure of dipyrrolylmethene and its aza analog on spectral-luminescent properties of heteroleptic boron(III) and homoleptic zinc(II) complexes with 3,3′,5,5′-tetramethyl-2,2′-dipyrrolylmethene, 3,3′,5,5′-tetraphenyl-2,2′-dipyrrolylmethene, and 3,3′,5,5′-tetraphenyl-ms-aza-2,2′-dipyrrolylmethene in organic solvent solutions was studied. The complexes were found to exhibit strong chromophore (λ = 350–690 nm, ? ~ 105 L/mol cm) and fluorescent properties. Quantum yield (γfl) for fluoroborate complexes reaches 100% and is weakly dependent on medium nature. The value of γfl for phenyl- and alkyl-substituted zinc(II) dipyrrolylmethenates in nonpolar solvents is not higher 0.3 and 0.03, respectively; complete fluorescence quenching is observed in electron-donating solvents. Aza-substitution at the meso spacer causes considerable shift of electronic absorption and fluorescence spectra to the red region but completely quenches fluorescence of zinc(II) chelates and decreases γfl of boron(III) complex to 0.04.  相似文献   

9.
New monodentate H8‐binaphthol based phosphoramidites 6 b–i have been prepared. Starting from (S)‐3,3′‐dibromo‐5,5′,6,6′,7,7′,8,8′‐octahydro‐1,1′‐binaphthyl‐2,2′‐diol 3 , a general protocol for the synthesis of ligands 6 is presented. A small ligand library bearing aryl substituents in the 3,3′‐position of the binaphthol core was synthesized and successfully tested in the iridium‐catalyzed asymmetric hydrogenation of 2‐amidocinnamates to obtain different α‐amino acid derivatives in up to 99 % ee.  相似文献   

10.
The Synthesis of 3,3′-bis(4-[3-ethynylphenoxy]phenyl)-7,7′-bis(phenylethynyl)-2,2′-diphenyl-6,6′-biquinoxaline (I) was accomplished by the reaction of 2,2′-bis(phenylethynyl)-5,5′-diaminobenzidine (II) and 4-(3-ethynylphenoxy)benzil. Thermal analysis of I indicated a softening temperature of 107°C, followed by an exotherm above 150°C that corresponded to a independent crosslinking reaction of the terminal acetylene groups and an intramolecular cycloaddition (IMC) reaction of the 2,2′-bis(phenylethynyl)biphenyl moieties. In the synthetic work substantial improvements were made in the synthesis of II. The sample of I was cured at 200°C and the maximum partially cured transition temperature attained was 280°C. A sample of 3,3′-bis(4,[3-ethynylphenoxy]phenyl)-2,2′-diphenyl-6,6′-biquinoxaline (IV) was similarly tested as a model without IMC capability and its corresponding value was 250°C. The difference between these two values is discussed briefly.  相似文献   

11.
Linear and branched conjugated pincer ligands having Ph2P groups were synthesized: 3,3',5,5'- tetrakis(diphenylphosphinomethyl)diphenylacetylene, 3,3',5,5'-tetrakis(diphenylphosphinomethyl)diphenyldi- acetylene, 1,3,5-tris[3,5-bis(diphenylphosphinomethyl)phenylethynyl]benzene, and hexakis[3,5-bis(diphenylphosphinomethyl)phenylethynyl]benzene. Palladation of these ligands by heating with Pd(BF4)2(MeCN)4 in boiling acetonitrile gave the corresponding di- and trinuclear ionic pincer palladium complexes. No individual complex was obtained from hexakis[3,5-bis(diphenylphosphinomethyl)phenylethynyl]benzene. The ionic com- plexes were converted into the corresponding chloride complexes by treatment with sodium chloride in a mixture of water with methylene chloride. The structure of the ionic palladium complex with 3,3',5,5'-tetrakis(diphenylphosphinomethyl)diphenylacetylene was established by X-ray analysis. The obtained palladium complexes exhibited a considerable catalytic activity in the Heck reaction of iodobenzene with ethyl acrylate and in the Michael addition of ethyl cyanoacetate with methyl vinyl ketone. The catalytic activity per palladium atom decreases as the number of palladium atoms in the complex increases.  相似文献   

12.
6,6′‐Dimethoxygossypolone (systematic name: 7,7′‐dihydroxy‐5,5′‐diisopropyl‐6,6′‐dimethoxy‐3,3′‐dimethyl‐1,1′,4,4′‐tetraoxo‐2,2′‐binaphthalene‐8,8′‐dicarbaldehyde), C32H30O10, is a dimeric molecule formed by oxidation of 6,6′‐dimethoxygossypol. When crystallized from acetone, 6,6′‐dimethoxygossypolone has monoclinic (P21/c) symmetry, and there are two molecules within the asymmetric unit. Of the four independent quinoid rings, three display flattened boat conformations and one displays a flattened chair/half‐chair conformation. The angles between the planes of the two bridged naphthoquinone structures are fairly acute, with values of about 68 and 69°. The structure has several intramolecular O—H...O and C—H...O hydrogen bonds and several weak intermolecular C—H...O hydrogen bonds, but no intermolecular O—H...O hydrogen bonds.  相似文献   

13.
郑绍军  谷永东  朱瑞  高健 《合成化学》2016,24(10):888-891
以3,4,5-三甲氧基苯甲酸为原料,经6步反应以23%总收率完成了Angustifolin D关键中间体--6,6′-2[(Z)-2-碘代-1-丙烯基]-2,2′,3,3′,4,4′-六甲氧基-1,1′-联苯(7)的合成,其结构经1H NMR, 13C NMR, IR和MS确证。其中关键步骤联苯偶连反应采用了廉价易得的铜试剂(CuBr·SMe2)作为催化剂。  相似文献   

14.
Redoxites poly(2,6-diphenyl-4-vinylpyran), poly(2,6-diphenyl-4-vinylpyrylium perchlorate), poly-(2,6-diphenyl-4-vinylpyridine) and poly(2,2′,6,6′-tetraphenyl-γ,γ′-dipyridine) were obtained based on pyrylium salts. Poly(2,2′,6,6′-tetraphenyl-γ,γ′-dipyridine) was transformed into the polyene to improve its film-forming and conducting properties. Electrochemical properties of polyviologen and conductive properties of the obtained polymers were studied.  相似文献   

15.
Poly(2,6-diphenyl-1,4-phenylene ether) reacts with phenols in the presence of an initiator to form a mixture of low molecular weight hydroxyarylene ethers. Although the reaction is similar to the equilibration of poly(2,6-dimethyl-1,4-phenylene ether) with phenols, higher reaction temperatures and larger initiator concentrations are required. Compounds as 3,3′,5,5′-tetraphenyl-4,4′-diphenoquinone, tert-butyl perbenzoate, and benzoyl peroxide are active initiators. The structure of the polymer affects the extent to which the polymer equilibrates.  相似文献   

16.
3,3′,4,4′‐Tetramethyl‐5,5′‐dioxo‐2,2′‐bifuran‐2,2′(5H,5′H) diyl diacetate was obtained from the reaction between 2,3‐dimethyl maleic anhydride and acetic anhydride in the presence of zinc in toluene. This easy synthetic route gave bis butenolide in excellent yield.  相似文献   

17.
A high-yield synthesis was developed for the preparation of 2,2'-bipyrimidine (1) using the Ullmann coupling of 2-iodopyrimidine. The new procedure was also used for the preparation of 4,4',6,6'-tetramethyl-2,2'-bipyrimidine (2) and 5,5'-dibromo-2,2'-bipyrimidine (3).  相似文献   

18.
The conjugate addition reactions of four organolithium reagents to 2,3,4,5-tetraphenylcyclopentadienone (tetracyclone) were investigated to reveal the reactivity of organolithium reagents to tetracyclone. The results show that 1,2-addition products 2,3,4,5-tetraphenyl-1-(2-thienyl)-2,4-cyclopentadien-1-ol(1), 1-n-butyl-2,3,4,5-tetraphenyl-2,4-cyclopentadien-1-ol(2) and 1,2,3,4,5-pentaphenyl-2,4-cyclopentadien-1-ol(3) were synthesized in excellent yields while tetracyclone reacted with 2-thienyllithium, n-butyllithium and phenyllithium, respectively. Interestingly, three 1,2-, 1,4- and 1,6-addition isomers 1-tert-butyl-2,3,4,5-tetraphenyl-2,4-cyclopentadien-1-ol(4), 4-tert-butyl-2,3,4,5-tetraphenyl-2-cyclopenten-l-one(5) and 2-tert-butyl-2,3,4,5-tetraphenyl-3-cyclopenten-l-one(6), were simultaneously obtained by the conjugate addition reaction of tert-butyllithium with larger steric hindrance to tetracyclone. Compounds 1-6 were characterized by 1H and 13C NMR spectra, Fourier transform infrared(FTIR) spectra and mass spectra(MS). The crystal and molecular structures of compounds 1, 2 and isomers 5, 6 were determined by X-ray single crystal diffraction technique. The results imply that the steric hindrance of tert-butyllithium probably play a key role in controlling the conjugate addition reaction. The conjugate addition mechanism of organolithium reagents to tetracyclone was proposed.  相似文献   

19.
Readily available 2,2',6,6'-tetramethoxy-1,1'-biphenyl was transformed in 14 synthetic steps into the natural product cardinalin 3 using a bidirectional approach. One of the key steps was the formation of the cis-1,3-dimethylnaphtho[2,3-c]pyran ring. (+/-)-1,1'-[6,6'-Diallyl-5,5'-bis(benzyloxy)-1,1',3,3'-tetramethoxy-2,2'-binaphthalene-7,7'-diyl]diethanol was treated with O(2) in the presence of CuCl(2) and catalytic PdCl(2) to afford 5,5'-bis(benzyloxy)-7,7',9,9'-tetramethoxy-1,1',3,3'-tetramethyl-1H,1'H-8,8'-bibenzo[g]isochromene. Hydrogenation of this compound afforded 7,7',9,9'-tetramethoxy-cis-1,3-cis-1',3'-tetramethyl-3,3',4,4'-tetrahydro-1H,1'H-8,8'-bibenzo[g]isochromene-5,5'-diol in quantitative yield, which was converted in 3 steps to cardinalin 3.  相似文献   

20.
Formylation of 2,2′,5′,2′-terfuran ( 1 ) with N-methylformanilide and phosphorus oxychloride gave 5-formyl-2,2′,5′,2′-terfuran ( 2 ) and 5,5′-diformyl-2,2′5′,2′-terfuran ( 3 ). Reduction of 2 and 3 afforded 5-hydroxymethyl-2,2′,5′,2′-terfuran ( 4 ) and 5,5′ dihydroxymethyl-2,2′,5′,2′-terfuran ( 5 ), respectively. Terfuran 1 reacted with phenylmagnesium bromide to give 5-(phenylhydroxymethyl)-2,2′,5′,2′-terfuran ( 6 ), and was carbonated to 5-carboxy 2,2′,5′,2′-terfuran ( 7 ) and 5,5′-dicarboxy-2,2′,5′,2′-terfuran ( 8 ). Bromination of 1 with N-bromosuccinimide gave 5,5′-dibromo 2,2′,5′,2′-terfuran ( 9 ).  相似文献   

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