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1.
A series of planar and non-planar (helical) thiophene-based polycyclic aromatics has been synthesized through the Diels-Alder reaction followed by decarbonylation reactions and FeCl3 oxidative cyclizations. 相似文献
2.
[reaction: see text] A variety of substituted polycyclic aromatics are readily prepared in good to excellent yields under very mild reaction conditions by the reaction of 2-(1-alkynyl)biphenyls with ICl, I(2), NBS, and p-O(2)NC(6)H(4)SCl. This methodology readily accommodates various functional groups and has been successfully extended to systems containing a variety of polycyclic and heterocyclic rings. 相似文献
3.
An efficient protocol for assembling a polycyclic spiroindoline scaffold is developed, which involves an intramolecular oxidative coupling of dianions derived from indole-embodied β-ketoamides using iodine as the oxidant, and subsequent attack of oxygen anion to the resultant imine moiety. A number of tetracyclic spiroindolines are prepared with moderate to good yields. 相似文献
4.
Chiral enediynes with pendant chiral amino ester groups are synthesized through Sonogashira reactions and subjected to thermal triggered Bergman cyclization at elevated temperatures either in bulk or in solvents to produce chiral polyphenylenes. The disappearance of enediyne monomers are evidenced by FTIR and NMR spectroscopies. The formation of polyphenylenes is further confirmed by UV-Vis and MALDI-TOF mass spectroscopies(MS). Isotope pattern analysis of the MS spectra shows that the polymers prepared in solvents are terminated by the solvent molecules, whereas the chain ends of the polymers prepared in bulk consist of considerable amount of unmasked free radicals, which is further confirmed by EPR analysis. Circular dichroism(CD) spectra of the chiral polymers show blue shifts of the Cotton peaks, indicating the occurrence of the cycloaromatization reaction. A new set of peaks mirrored at the horizontal axis show up in the long wavelength range, which are assigned to main chain chirality of the polyphenylenes. 相似文献
5.
Wegner HA Reisch H Rauch K Demeter A Zachariasse KA Meijere Ad Scott LT 《The Journal of organic chemistry》2006,71(24):9080-9087
A new class of polycyclic aromatic hydrocarbons--oligoindenopyrenes--has been synthesized featuring a Pd-catalyzed Suzuki-Heck coupling cascade. The oligoindenopyrenes are robust, highly colored substructures of C(70) and have properties that might prove useful in new organic materials or devices. After excitation, the tetraindenopyrene derivative 3d undergoes efficient deactivation (99%) by internal conversion to the ground state. The small fluorescence quantum yield (0.004) is in accordance with the short (0.6 ns) fluorescence decay time. 相似文献
6.
Larry J. Baldwin Marvin L. Tedjamulia John G. Stuart Raymond N. Castle Milton L. Lee 《Journal of heterocyclic chemistry》1984,21(6):1775-1779
The synthesis of benzo[b]triphenyleno[2,1-d]thiophene ( 9 ), benzo[b]triphenyleno[1,2-d]thiophene ( 13 ), 5-methylbenz[7,8]anthra[2,1-b]thiophene ( 17 ), l-methylchryseno[3,4-b]thiophene ( 18 ), triphenyleno[1,2-c]dibenzothiophene ( 22 ), triphenyleno[2,1-a]dibenzothiophene ( 26 ), triphenyleno[1,2-a]dibenzothiophene ( 29 ), and triphenyleno[2,1-b]dibenzothiophene ( 30 ) is described. 相似文献
7.
A tetra-butylammonium iodide (TBAI)-mediated oxidative iodocyclization of 2-alkynoates for the synthesis of various 4-iodoisocoumarin is described herein, and the reaction is highly efficient and shows broad functional group tolerance. This newly developed reaction uses a mixture of water and DCE as co-solvent, and avoids the use of iodine as iodine source for the electrophilic halocyclization. 相似文献
8.
Hirotaka Kudo Marvin L. Tedjamulia Raymond N. Castle Milton L. Lee 《Journal of heterocyclic chemistry》1984,21(1):185-192
We describe the synthesis of thieno[2,3-c]dibenzothiophene ( 6 ), thieno[3,2-c]dibenzothiophene ( 10 ), thieno-[3,2-a]dibenzothiophene ( 14 ), thieno[2,3-a]dibenzothiophene ( 16 ), benzo[1,2-b:4,3-b]bisbenzo[b]thiophene ( 18 ), benzo[1,2--6:3,4-b]bisbenzo[b]thiophene ( 20 ), benzo[2,1--6:3,4-b]bisbenzo[b]thiophene ( 22 ), benzo[1,2-b:3,4-g]bisbenzo[b]thiophene ( 27 ), benzo[1,2-b:4,3-e]bisbenzo[b]thiophene ( 29 ), benzo[2,1--6:3,4-g]bisbenzo[b]thiophene ( 36 ), benzo[2,1--6:4,3-e]bisbenzo[b]thiophene ( 38 ), benzo[1,2--6:4,3-g]bisbenzo[b]thiophene ( 41 ), benzo[1,2-b:4,5-g]bisbenzo[b]thiophene ( 42 ), benzo[1,2-b:3,4-e]bisbenzo[b]thiophene ( 44 ) and benzo-[1,2-b:5,4-e]bisbenzo[b]thiophene ( 45 ). 相似文献
9.
The syntheses of novel thieno‐pyridones, thiazolo‐pyridones, thiazolo‐pyridines and amino‐ and diamino‐dieno‐pyridines were described. Simultaneously, it was demonstrated that in these compounds and in the related 3‐aminothiophenes the replacement of the methylthio by the morpholino group is possible. The structures were characterized using 1H‐, 13C‐NMR, IR and elemental analysis. 相似文献
10.
11.
《Tetrahedron》1986,42(8):2185-2192
12.
《Journal of organometallic chemistry》2004,689(11):1919-1929
Reduction of methyl-substituted titanocene dichlorides bearing pendant double bonds [TiCl2{η5-C5Me4(CH2CMeCH2)}2] (1) and [TiCl2{η5-C5Me4(SiMe2(CH2)2CHCH2)}2] (2) with magnesium yielded diamagnetic Ti(IV) compound [Ti{η1:η1:η5-C5Me3(CH2)(CH2CH(Me)CH2)}{η5-C5Me4(CH2C(Me)CH2)}] (4) and paramagnetic Ti(III) compound [Ti{η5-C5Me4(SiMe2CH2CHCHMe)}(μ-η3,η1:η5,η1(Ti:Mg){C5Me3(CH2)(SiMe2CHCHCMe)})Mg(OC4H8)2] (6), respectively. The reluctance of titanocene intermediates to undergo intramolecular cyclization to cyclopentadienyl-ring-tethered titanacycles (as typically observed) can be explained by a shortness of the 2-methylallyl group and steric hindrance of its double bond in the former case and, in the latter case, by an attack of magnesium on the titanocene intermediate, faster than cyclization reactions. The crystal structures of 4 and 6 were determined by single-crystal X-ray diffraction. 相似文献
13.
Ana Flávia Borsoi Mateus Emanuel Coldeira Kenia Pissinate Fernanda Souza Macchi Luiz Augusto Basso 《合成通讯》2017,47(14):1319-1325
A ultrasound-assisted oxidative cyclization of semicarbazones using N-bromosuccinimide in the presence of sodium acetate was established providing efficient and rapid access to a variety of 2-amino-1,3,4-oxadiazoles. Moreover, the new synthetic protocol provides a simple procedure utilizing a safer oxidizing system that affords the target products in high regioselectivity, satisfactory yields, and elevated purities. 相似文献
14.
Marvin L. Tedjamulia Hirotaka Kudo Raymond N. Castle Milton L. Lee 《Journal of heterocyclic chemistry》1984,21(2):321-325
The syntheses of naphtho[1,2–6:7,6-b′]bisbenzo[b]thiophene ( 4 ), naphtho[1,2–6:7,8-b′]bisbenzo[b]thiophene ( 5 ), naphtho[2,1-b:7,6-b′]bisbenzo[b]thiophene ( 8 ), naphtho[2,1-b:7,8-b′]bisbenzo[b]thiophene ( 9 ), naphtho-[1,2–6:5,6-b′]bisbenzo[b]thiophene ( 14 ), naphtho[1,2–6:6,5-b]bisbenzo[b]thiophene ( 17 ) and naphtho[2,1–6:-6,5-b′]bisbenzo[b]thiophene ( 23 ) are reported. 相似文献
15.
Polycyclic aromatics with various functional group (e.g. OH, OR, SR, and halogen) were easily defunctionalized by aluminum chloride and ethanethiol to give parent aromatics in high yields under mild conditions. This reaction proceeds through sulfide as the intermediate, hence it is also useful for the synthesis of sulfides of polycyclic aromatics. 相似文献
16.
17.
Levine DR Caruso A Siegler MA Tovar JD 《Chemical communications (Cambridge, England)》2012,48(50):6256-6258
The synthesis of new boron-containing acenes (meta-B-entacenes) is reported. These compounds exhibit slightly non-planar core geometries with blue-shifted spectral properties and more negative electrochemical reduction potentials relative to known para isomers. Polarizable π-extended architectures were realized via cross-coupling procedures with chloro-functionalized precursors. 相似文献
18.
Partial fluorination overcomes herringbone crystal packing in small polycyclic aromatics 总被引:1,自引:0,他引:1
[structure: see text] We report the synthesis and characterization of partially fluorinated condensed tetracyclic aromatic compounds. Typical edge-to-face/herringbone packing of nonfluorinated analogues is replaced here by columnar stacks with disk planes orthogonal to the columnar axes. Enhanced pi-overlap results with overlaid electron-poor and -rich regions. 相似文献
19.
Hatakeyama T Hashimoto S Seki S Nakamura M 《Journal of the American Chemical Society》2011,133(46):18614-18617
A tandem intramolecular electrophilic arene borylation reaction has been developed for the synthesis of BN-fused polycyclic aromatic compounds such as 4b-aza-12b-boradibenzo[g,p]chrysene (A) and 8b,11b-diaza-19b,22b-diborahexabenzo[a,c,fg,j,l,op]tetracene. These compounds adopt a twisted conformation, which results in a tight and offset face-to-face stacking array in the solid state. Time-resolved microwave conductivity measurements prove that the intrinsic hole mobility of A is comparable to that of rubrene, one of the most commonly used organic semiconductors, indicating that BN-substituted PAHs are potential candidates for organic electronic materials. 相似文献
20.
Zhiguo Zhang Xiaoqing Song Guofeng Li Xiang Li Dan Zheng Xuna Zhao Huanran Miao Guisheng Zhang Lantao Liu 《中国化学快报》2021,32(4):1423-1426
We report a 2-iodoxybenzoic acid (IBX)-mediated intarmolecular oxidative spiro-fused tandem cyclization reaction of tryptophan analogs bearing an N-arylamides side-chain to rapidly afford polycyclic spiroindolines featuring multiple stereocenters including a quaternary stereocenters under mild reaction conditions. Among them, a novelty azaphosphol idine-containing spiroindoline compound is synthesized for the first time. It may open the door to azaphos pholidine-containing spiroindoline compound of potential interest in synthetic and medicinal chemistry. A plausible mechanism is proposed. 相似文献