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1.
Nickel‐Catalyzed Cross‐Electrophile Coupling with Organic Reductants in Non‐Amide Solvents 下载免费PDF全文
Dr. Lukiana L. Anka‐Lufford Kierra M. M. Huihui Dr. Nicholas J. Gower Dr. Laura K. G. Ackerman Prof. Dr. Daniel J. Weix 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(33):11564-11567
Cross‐electrophile coupling of aryl halides with alkyl halides has thus far been primarily conducted with stoichiometric metallic reductants in amide solvents. This report demonstrates that the use of tetrakis(dimethylamino)ethylene (TDAE) as an organic reductant enables the use of non‐amide solvents, such as acetonitrile or propylene oxide, for the coupling of benzyl chlorides and alkyl iodides with aryl halides. Furthermore, these conditions work for several electron‐poor heterocycles that are easily reduced by manganese. Finally, we demonstrate that TDAE addition can be used as a control element to ‘hold’ a reaction without diminishing yield or catalyst activity. 相似文献
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By this article we conclude the construction of all primitive ( v, k,λ ) symmetric designs with v < 2500 , up to a few unsolved cases. Complementary to the designs with prime power number of points published previously, here we give 55 primitive symmetric designs with v ≠ p m , p prime and m positive integer, together with the analysis of their full automorphism groups. The research involves programming and wide‐range computations. We make use of the software package GAP and the library of primitive groups which it contains. © 2011 Wiley Periodicals, Inc. J Combin Designs 19:463‐474, 2011 相似文献
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The reaction of 3-acylsubstituted 2H-1-benzo-pyran-2-ones 1, 5 and 11a-c with acid anhydrides in the presence of potassium fluoride (KF)/molecular sieves 4A gives the 4-(2-oxoalkyl)-2-oxochromans 2, 6 and 12a-c as the main products. Also the 3-carboxylic acid derivatives, such as esters and N,N-dialkylamides, of 2H-1-benzopyran-2-one (11d-g) react with isobutyric acid anhydride in the presence of KF/molecular sieves 4A to give the corresponding 2-oxochroman-4-acetic acid derivatives. 相似文献
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In two groups of order 100 new difference sets are constructed. The existence of a difference set in one of them has not been known. The correspondence between a (100, 45, 20) symmetric design having regular automorphism group and a difference set with the same parameters has been used for the construction. © 2001 John Wiley & Sons, Inc. J Combin Designs 9: 424–434, 2001 相似文献
6.
Aleksandra Minić Jovana P. Bugarinović Anka Pejović Danijela Ilić Komatina Goran A. Bogdanović Ivan Damljanović Dragana Stevanović 《Tetrahedron letters》2018,59(38):3499-3502
A simple one-pot synthesis of new ferrocene-containing 1,3-thiazinan-2-imines from 3-arylamino-1-ferrocenylpropan-1-ols and phenyl isothiocyanate has been developed. The key intermediate β-hydroxy thioureas were generated in situ using ultrasound irradiation and subsequent cyclization was achieved by the addition of acetic acid. The scope of the reaction towards various 3-arylamino-1-ferrocenylpropan-1-ols has been explored and the corresponding 3-aryl-6-ferrocenyl-N-phenyl-1,3-thiazinan-2-imines were obtained in moderate to high yields (52–90%). 相似文献
7.
B. B. Koleva R. D. Nikolova S. Zareva T. Kolev A. G. Bojilova H. Mayer-Figge W. S. Sheldrick 《Structural chemistry》2008,19(6):975-982
IR-spectroscopic characterization of the coumarin-3-phosphonic acid and 1,2-benzoxaphosphorine-3-carboxylic acid ethyl esters has been carried out by means of linear-polarized IR (IR-LD) spectroscopy of oriented colloid suspensions in a nematic host. Quantum chemical DFT calculations at the B3LYP level of theory and 6-311++G** basis set were performed. The electronic structure and vibrational properties of both compounds are discussed. The spectroscopic data for 2-benzoxaphosphorine-3-carboxylic acid ethyl ester are in accordance with the crystal structure determined by single crystal X-ray diffraction. The compound C13H15O5P crystallizes in the noncentrosymmetric space group P212121, and its structure consists of a 3D network formed by short contacts of the type P=O···HC(Ar) with distances of 3.420 and 2.467 Å. The geometry of the PO3C fragment exhibits a pseudo T d symmetry. 相似文献
8.
Ljubo Golič Jože Slivnik Marjan Levstek Anka Rihar 《Monatshefte für Chemie / Chemical Monthly》1968,99(1):289-290
Ohne Zusammenfassung 相似文献
9.
Zusammenfassung Es wurden die Verbindungen N2H5[Sc(N2H3COO)4]·3 H2O und Y(N2H3COO)3·3 H2O isoliert und untersucht. Es wird auf die interessante Koordinationszahl 8 in der komplexen Scandium-Verbindung hingewiesen. Die Yttrium-Verbindung zeigt eine Ähnlichkeit mit der schon bekannten Lanthan-Verbindung, beide kann man als einfache hydratisierte Salze der Hydrazido-Kohlensäure auffassen.
Teil eines Referates auf dem I. jugoslawischen Kongreß für Industrie-Chemie in Beograd, Juni 1969. 相似文献
Synthesis of Sc and Y compounds of hydraziniumcarboxylic acid
The compounds N2H5[Sc(N2H3COO)4]·3 H2O and Y(N2H3COO)3·3 H2O have been isolated and investigated. The scandium compound shows an interesting coordination number (8). The yttrium compound is related to the already known lanthanum compound—both are hydrated simple salts of hydraziniumcarboxylic acid.
Teil eines Referates auf dem I. jugoslawischen Kongreß für Industrie-Chemie in Beograd, Juni 1969. 相似文献
10.
Cathryn G. Conner Anka N. Veleva Vesselin N. Paunov Simeon D. Stoyanov Orlin D. Velev 《Particle & Particle Systems Characterization》2020,37(7):2000122
A highly controllable and scalable process for fabrication of large amounts of concentrated lignin nanoparticles (LNPs) is reported. These lignin core nanoparticles are formed through flash nanoprecipitation, however, scaling up of the fabrication process requires fundamental understanding of their operational formation mechanism and surface properties. It is shown how a semicontinuous synthesis system with a recirculation loop makes it possible to produce flash precipitated lignin nanoparticles in large amounts for practical applications. The roles of the process parameters, including flow rates and lignin concentration, are investigated and analyzed. The results indicate that the LNPs are formed by a process of continuous burst nucleation at the point of mixing without diffusive growth, which yields nanoparticles of highly uniform size following a modified LaMer nucleation and growth mechanism. This mechanism makes possible facile process control and scale-up. Effective control of the resulting nanoparticle size is achieved through the initial concentration of lignin in the injected solution. The impressive capability to produce suspensions of any predesigned multimodal distribution is demonstrated. The resulting nanofabrication technique can produce large volumes of concentrated LNP suspensions of high stability and tightly controlled size distributions for biological or agricultural applications. 相似文献