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91.
Anwar Jacintomoreno Dr. Hemant K. Sharma Dr. Alejandro Metta-Magaña Prof. Dr. Keith H. Pannell 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(48):11302-11307
The reactions of the Mannich reagent Et3SiOCH2NMe2 ( 1 ) with a variety of anilines (mono-substituted RC6H4NH2, R=H, 4-CN, 4-NO2, 4-Ph, 4-Me, 4-MeO, 4-Me2N; di-substituted R2C6H3NH2, R2=3,5-(CH3)2, 3,5-(CF3)2; tri-substituted R3C6H2NH2, R3=3,5-Me2-4-Br and a “super bulky” aniline (Ar*NH2) [Ar*=2,6-bis(diphenylmethyl)-4-tert-butylphenyl]) led to the formation of a range of products dependent upon the substituent. With electron-withdrawing substituents, previously unknown diamines, RC6H4NH(CH2NMe2) [R=CN ( 2 a ), NO2 ( 2 b )] and R2C6H3NH(CH2NMe2) [R2=3,5-(CF3)2 ( 2 c) ] were formed. Further reaction of 2 a , b , c with 1 yielded the corresponding triamines RC6H4N(CH2NMe2)2 (R=CN ( 3 a ), NO2 ( 3 b ) and R2C6H3N(CH2NMe2)2, R2=3,5-(CF3)2 ( 3 c ). The new polyamines were characterized by NMR spectroscopy, and for 2 a , 2 c , and 3 c , by single crystal XRD. In the case of electron-donating groups, R=4-OMe, 4-NMe2, 4-Me, 3,5-Me2, 3,5-Me2-4-Br, and for R=4-Ph, the reactions with 1 immediately led to the formation of the related 1,3,5-triazines, R=4-MeO ( 5 a ), 4-Me2N ( 5 b ), 4-Me ( 5 c ), 3,5-Me2 ( 5 d ), 3,5-Me2-4-Br ( 5 e ), 4-Ph ( 5 f ), 4-Cl ( 5 g ). The “super bulky” aniline rapidly produced a single product, namely the corresponding imine Ar*N=CH2 ( 4 ) which was also characterized by single crystal XRD. Imine 4 is both thermally and oxidatively stable. All reactions are very fast, thus based upon the presence of Si we are tempted to denote the reactions of 1 as examples of “Silick” chemistry. 相似文献
92.
Dr. Waqar Rizvi Naxhije Berisha Dr. Christopher Farley Dr. N. V. S. Dinesh K. Bhupathiraju Dr. Chrysafis Andreou Emaad Khwaja German V. Fuentes Dr. Moritz F. Kircher Dr. Ruomei Gao Dr. Charles Michael Drain 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(64):14517-14521
Distortion of nominally planar phthalocyanine macrocycles affects the excited state dynamics in that most of the excited-state energy decays through internal conversion. A click-type annulation reaction on a perfluorophthalocyanine platform appending a seven-membered ring to the β-positions on one or more of the isoindoles distorts the macrocycle and modulates solubility. The distorted derivative enables photoacoustic imaging, photothermal effects, and strong surface-enhanced resonance Raman signals. 相似文献
93.
Bülbül Hakan Köysal Yavuz Doğan Onur Erman Dege Necmi Ağar Erbil 《Crystallography Reports》2019,64(3):403-406
Crystallography Reports - The title compound, C17H15NOS, crystallizes in the orthorhombic sp. gr. Pca21. Two molecules in the asymmetric unit have similar structure. Crystal structure contains weak... 相似文献
94.
Sharma Deepak Sharma Naresh Brahmbhatt D. I. Gupta Vivek K. 《Crystallography Reports》2019,64(7):1047-1050
Crystallography Reports - The crystal structure of the title compound is determined by single crystal X-ray structure analysis. The structure was solved by direct method and refined to a final... 相似文献
95.
Kiruthika S. Malathi M. Selvasekarapandian S. Tamilarasan K. Moniha V. Manjuladevi R. 《Journal of Solid State Electrochemistry》2019,23(7):2181-2193
Journal of Solid State Electrochemistry - Current research on electrochemical device application focuses on the usage of biopolymers like chitosan, pectin, agar-agar, cellulose acetate, and... 相似文献
96.
Ambarish Mondal Rajat K. Tripathy Parul Dutta Manas Kumar Santra Anvarhusein A. Isab Christopher W. Bielawski Hemanta K. Kisan Swapan K. Chandra Joydev Dinda 《应用有机金属化学》2019,33(1)
The syntheses, structures, and chemotherapeutic activities of Ag(I)‐, Au(I)‐, and Ru(II)‐complexes ligated to a novel N‐heterocyclic carbene ligand, 2‐(4‐nitrophenyl)imidazo[1,5‐a]pyridin‐2‐ylidene ( 1 ), are described. The corresponding complexes, [Ag( 1 )2][PF6], [Au( 1 )2][PF6] ( 3 ), and [Ru( 1 )(p‐cymene)Cl][PF6] ( 4 ), were prepared using convenient transmetallation chemistry and characterized using a range of spectroscopic and analytical techniques. X‐ray crystallography revealed that complexes 2 and 3 adopted linear structures whereas 4 exhibited a prototypical “piano‐stool”‐like geometry; the structural assignments were further supported by DFT calculations. A series of in vitro studies revealed that while the aforementioned Ag(I), Au(I) and Ru(II) complexes exhibited significant cytotoxicities against the human colon adenocarcinoma (HCT 116), lung cancer (A549), and breast cancer (MCF7) cell lines, the Ru derivative was most prominent. 相似文献
97.
Vokhmintcev A. V. Melnikov A. V. Mironov K. V. Burlutskiy V. V. 《Doklady Mathematics》2019,99(1):108-112
Doklady Mathematics - A closed-form solution is proposed for the problem of minimizing a functional consisting of two terms measuring mean-square distances for visually associated characteristic... 相似文献
98.
Eric C. Chi Liuyi Hu Arvind K. Saibaba Arvind U. K. Rao 《Journal of computational and graphical statistics》2019,28(1):36-47
We consider the problem of performing matrix completion with side information on row-by-row and column-by-column similarities. We build upon recent proposals for matrix estimation with smoothness constraints with respect to row and column graphs. We present a novel iterative procedure for directly minimizing an information criterion to select an appropriate amount of row and column smoothing, namely, to perform model selection. We also discuss how to exploit the special structure of the problem to scale up the estimation and model selection procedure via the Hutchinson estimator, combined with a stochastic Quasi-Newton approach. Supplementary material for this article is available online. 相似文献
99.
Pawar Umakant D. Pawar Chandrakant D. Mavle Rajendra R. Pardeshi Rajendra K. 《平面色谱法杂志一现代薄层色谱法》2019,32(5):435-437
JPC – Journal of Planar Chromatography – Modern TLC - A novel chromogenic reagent was developed for the identification and detection of organophosphorus herbicide. The organophosphorus... 相似文献
100.
Smolobochkin A. V. Gazizov A. S. Matylitskii K. V. Vagapova L. I. Burilov A. R. Pudovik M. A. 《Russian Journal of General Chemistry》2019,89(9):1934-1938
Russian Journal of General Chemistry - The acid-catalyzed reaction of {2-[1-(2,2-dimethoxyethyl)-3-(phenylcarboxamido)]ethyl}phosphonate or diethyl... 相似文献