3777-70-6Relevant academic research and scientific papers
Synthesis and properties of anti/syn-regioisomeric mixtures of alkyl-substituted tetracenes
Kitamura, Chitoshi,Kano, Hiroyuki,Tsukuda, Hideki,Kawase, Takeshi,Kobayashi, Takashi,Naito, Hiroyoshi
, p. 1621 - 1629 (2011)
We prepared anti/syn-regioisomeric mixtures of alkyl-substituted tetracenes via Diels-Alder reaction between asymmetric furans and 2,6-naphthodiyne synthon. The solid-state color of the mixtures changed before and after recrystallization from Et2O, suggesting a difference in the molecular arrangements dependent on the different alkyl substituents as well as the change in the distribution of the anti/syn regioisomers after recrystallization. Slow evaporation of the recrystallized mixtures produced single crystals suitable for X-ray analysis, which revealed that the anti regioisomer was isolated. The Japan Institute of Heterocyclic Chemistry.
Singlet-Oxygen-Initiated Tandem Transformation of 2-Hexylfuran to the Natural Alkaloids Glochidine and Glochidicine
Ioannou, Georgios I.,Kalaitzakis, Dimitris,Vassilikogiannakis, Georgios
, p. 3304 - 3306 (2016)
A synthesis of the imidazole alkaloids glochidine and glochidicine is presented. These natural products were prepared by the photooxygenation of a readily accessible alkylfuran precursor using histamine as a nitrogen source. By tailoring the choice of the photosensitizer as well as the conditions used for the cyclization of an N-acyliminium intermediate, the tandem reaction sequence could be manipulated to afford each of the natural products independently and as desired.
The function of Chalcogenophene in the Cyclomatelated Ring of the Cycloruthenated Dyes applied in Dye-Sensitized Solar Cell
Nguyen, The-Duy,Lan, Yen-Po,Wu, Chun-Guey
supporting information, p. 11328 - 11337 (2021/08/03)
Three thiocyanate-free cycloruthenated complexes, DUY24-O, DUY24, and DUY24-Se containing furan, thiophene, and selenophene, respectively, as a part of the cycloruthenated ring, were designed to reveal the function of the chalcogen atom on the physicochemical and photovoltaic performance of the cycloruthenated sensitizers applied in dye-sensitized solar cells (DSCs). The three sensitizers have a similar molecular size; therefore, the effect of molecular dimensions on their photovoltaic performance can be negligible. NMR data, electron-donating resonance effects, optical properties, and the energy levels of the frontier orbitals reveal that the physical/photovoltaic properties of the three sensitizers were affected significantly by the chalcogen atom on the cyclometalated chalcogenophene ring. The λmax (both in ethanol and adsorbed on TiO2), frontier orbital level, and dye loading of thiophene- and selenophene-containing dyes are very close. Nevertheless, DUY24-Se has a higher molar absorption coefficient compared to DUY24; therefore, the DSC based on DUY24-Se has higher efficiency (8.4% under AM1.5 G one-sun and 26% under T5-light at ca. 6000 lux) than that sensitized with the DUY24 dye. These efficiencies are also higher than those (7.9 and 21.6%, respectively) of the cell dyed with N719, fabricated using the same conditions. The better performance of the device sensitized with DUY24-Se compared to DUY24-based cells suggests that selenophene is as good as (or even better than) thiophene to be a part of the cyclometalated ring for thiocyanate-free cycloruthenated sensitizers applied in DSCs. Furan-containing DUY24-O has much worse photovoltaic performance compared to the other two dyes. This is not only because DUY24-O has the shortest λmax, the lowest molar absorption coefficient, and the highest HOMO level but also the lowest dye loading (because of the strong interaction between the oxygen in furan and TiO2, the array of DUY24-O occupies more surface when adsorbed on TiO2) and the fastest charge recombination. The physicochemical and photovoltaic properties as well as the adsorption behavior of the dye on the TiO2 anode for the cycloruthenated sensitizers affected significantly by the chalcogen atom of the chalcogenophene on the cyclometalated ring provide a new strategy to design high-efficiency NCS-free cyclometalated sensitizers for DSCs.
Cytotoxic polyacetylenes isolated from the roots and rhizomes of Notopterygium incisum
Zheng, Xikang,Zheng, Xiaoqing,Zhang, Chen,Zhang, Qingying,Jiang, Yong,Tu, Pengfei
supporting information, p. 428 - 430 (2018/11/27)
Phytochemical investigation on the roots and rhizomes of Notopterygium incisum led to the isolation of a new polyacetylene, notopolyenol A (1), along with thirteen known analogues (2–14). Their structures were elucidated by extensive analyses of NMR and HRMS data, and the absolute configuration of 1 was unambiguously determined as 3R by comparison of its retention time and ECD curve with those of synthetic enantiomers (?)-1 and (+)-1, whose absolute configurations were established by using the modified Mosher's method. Subsequent activity screening revealed that (3S)-1 exhibited the most significant cytotoxicity against MCF-7, H1299, and HepG2 cancer cells with IC50 values of 1.3 μmol/L, 0.6 μmol/L and 1.4 μmol/L, respectively.
Nickel complex catalyzed efficient activation of sp3and sp 2c-h bonds for alkylation and arylation of oxygen containing heterocyclic molecules
Gartia, Yashraj,Ramidi, Punnamchandar,Jones, Darin E.,Pulla, Sharon,Ghosh, Anindya
, p. 507 - 515 (2014/06/24)
A nickel(II) complex (1) of N,N'-bis(2,6-diisopropylphenyl)-2,6- pyridinedicarboxamido (L) ligand was examined for catalytic coupling of Grignard reagents with the C-H bond of oxygen containing heterocyclic compounds such as tetrahydrofuran and furan. The nickel( II) complex showed excellent activity in catalyzing C-H activation and further coupling with various Grignard reagents. The effective activation of the C-H bond proceeded under ambient reaction conditions with a short reaction time (1-2 h). The catalyst (1) displays high turnover frequency of 4,130 h-1with catalyst loading as low as 0.01 mol%. This catalytic route could prove to be an efficient mode of activation of sp3and sp2C-H bonds in various heterocycles for the preparation of synthetically and pharmaceutically relevant molecules. Springer Science+Business Media New York 2013.
Activation of sp3 and sp2 C-H bonds of oxygen containing heterocyclic molecules for alkylation and arylation reactions catalyzed by an iron complex
Gartia, Yashraj,Ramidi, Punnamchandar,Cheerla, Sreevishnu,Felton, Charlette M.,Jones, Darin E.,Das, Bhaskar C.,Ghosh, Anindya
, p. 253 - 259 (2014/07/07)
Activation of both sp3 and sp2 CH bonds is reported using an efficient iron(III) complex (1) of a ligand (N2,N6-bis(2,6- diisopropylphenyl)pyridine-2,6-dicarboxamide: L). The iron(III) complex showed catalytic activity of CC coupling reaction of oxygen containing heterocycles, e.g. tetrahydrofuran (THF), with various alkyl, allyl and aryl Grignard reagents under ambient reaction conditions. Complex 1 demonstrated excellent activity and reactions were completed within 30 min to 1 h. A high turnover frequency (TOF) of 1700 h-1 using a low catalyst loading of 0.02 mol% was obtained for the reaction. Interestingly, the catalyst was selective in activation of the CH bond adjacent to the oxygen in various oxygen containing heterocyclic molecules to yield 2-substitituted products.
Leveraging the micellar effect: Gold-catalyzed dehydrative cyclizations in water at room temperature
Minkler, Stefan R. K.,Isley, Nicholas A.,Lippincott, Daniel J.,Krause, Norbert,Lipshutz, Bruce H.
, p. 724 - 726 (2014/03/21)
The first examples of gold-catalyzed cyclizations of diols and triols to the corresponding hetero- or spirocycles in an aqueous medium are presented. These reactions take place within nanomicelles, where the hydrophobic effect is operating, thereby driving the dehydrations, notwithstanding the surrounding water. By the addition of simple salts such as sodium chloride, reaction times and catalyst loadings can be significantly decreased.
Reductive ring cleavage of nonconjugated Δ2-isoxazolines to β-hydroxy ketones with aluminum and copper(II) chloride
Karpaviiene, Ieva,Lapinskaite, Ringailé,Bruktus, Algirdas,Cikotiene, Inga
experimental part, p. 381 - 384 (2012/03/27)
A facile, economic, and efficient protocol for the reduction of nonconjugated Δ2-isoxazolines to the corresponding β-hydroxy ketones using Al/CuCl2 as the reducing agent has been developed. The method is both rapid and complete requiring less than ten minutes to attain total ring cleavage. This is the first example of using an in situ prepared Al/Cu couple in organic synthesis. Georg Thieme Verlag Stuttgart · New York.
Amino acid catalysis of 2-alkylfuran formation from lipid oxidation-derived α,β-unsaturated aldehydes
Adams, An,Bouckaert, Capucine,Van Lancker, Fien,De Meulenaer, Bruno,De Kimpe, Norbert
experimental part, p. 11058 - 11062 (2012/02/06)
The formation of 2-alkylfurans from the corresponding lipid-derived α,β-unsaturated aldehydes under dry-roasting conditions was investigated in detail. The addition of an amino acid to an α,β- unsaturated aldehyde drastically increased 2-alkylfuran formation. Peptides and proteins as well were able to catalyze 2-alkylfuran formation from the corresponding α,β-unsaturated aldehydes. Further investigation of 2-alkylfuran formation showed the need of oxidizing conditions and the involvement of radicals in the reaction. This way, the formation of 2-methylfuran from 2-pentenal, 2-ethylfuran from 2-hexenal, 2-propylfuran from 2-heptenal, 2-butylfuran from 2-octenal, 2-pentylfuran from 2-nonenal, and 2-hexylfuran from 2-decenal was shown. The impact of amino acids on 2-alkylfuran formation from lipid-derived α,β-unsaturated aldehydes represents an interesting example of the complex role of amino acids in the multitude of chemical reactions occurring during thermal processing of lipid-rich foods.
(2E)-4-hydroxyalk-2-enals and 2-substituted furans as products of reactions of (2E)-4,4-dimethoxybut-2-enal with Grignard compounds
Garibyan,Ovanesyan,Makaryan,Petrosyan,Chobanyan
experimental part, p. 406 - 409 (2010/09/12)
Methods have been developed for the synthesis of (2E)-1,1-dimethoxyalk-2- en-4-ols and (2E)-4-hydroxyalk-2-enals by reaction of (2E)-4,4-dimethoxybut-2- enals and Grignard compounds. Thermal isomerization of (2E)-4-hydroxyalk-2-enals gave the corresponding 2-alkylfurans.
