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71.
Russian Journal of General Chemistry - O-Silylurethanes have been synthesized in up to 87% yield via the reaction of tin tetracarbamates with organyl chlorosilanes in the presence of tertiary amines. 相似文献
72.
73.
Masaharu Ueno Satoshi D. Ohmura Makoto Wada Norikazu Miyoshi 《Tetrahedron letters》2019,60(7):570-573
We developed an environmentally friendly method for aerobic oxidation of alcohols using a commercially available, relatively benign bismuth salt as a catalyst. We found that the catalytic combination of BiBr3 with nitric acid is key for enhancing the reactivity. The reaction proceeds well under air, making the use of pure oxygen unnecessary. Each of the primary or secondary alcohols tested was oxidized to the corresponding aldehydes or ketones using this protocol. 相似文献
74.
Denis D. Borisov Grigory R. Chermashentsev Roman A. Novikov Yury V. Tomilov 《Tetrahedron letters》2019,60(10):746-750
New “four-component” self-assembly of polyaromatic thiophene structures based on styrylmalonates and 5-phenylthiophene-2-carbaldehyde has been developed. This process is promoted by GaCl3 and involves two [2?+?3]-annulation steps on the CHO-groups and para-substitution into one Ph-ring. The main feature of discovered process is a high diastereoselectivity with a significant increase in molecular complexity. The resulting polyaromatic structures containing two thiophene moieties in each structure have intense color and strong absorption in a near UV spectral region with absorption maxima in the range of 257–360?nm. 相似文献
75.
Sorokin V. M. Konoshchuk N. V. Khmil D. M. Posudievsky O. Yu. Koshechko V. G. Pokhodenko V. D. 《Theoretical and Experimental Chemistry》2019,55(4):223-231
Theoretical and Experimental Chemistry - A new method is proposed for the formation of MAPbBr3 nanoparticles in situ in a dispersion of polystyrene in toluene in the absence (MAPbBr3@PS) and... 相似文献
76.
Nonlinear Dynamics - The development of efficient computational methods for cracked structures is critical in the fields of civil, mechanical, and aerospace engineering since the influence of... 相似文献
77.
Accreditation and Quality Assurance - When reporting expanded uncertainty, rounding the number of significant figures can affect the associated level of confidence. A simple numerical method is... 相似文献
78.
Iain D. H. Oswald 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(8):1021-1022
A new crystalline form of αβ‐d ‐lactose prepared by oven drying a concentrated aqueous solution of d ‐lactose is a lesson in the power of observation and the rigorous analysis of powder samples. 相似文献
79.
Joseph D. Martin 《Annalen der Physik》2019,531(10)
Mildred Dresselhaus is known for her influential research on the physics of carbon. Her wide‐ranging influence as a physics teacher, although well‐known to her students, has been less thoroughly examined. Exploring how Dresselhaus grew into her role teaching solid state physics at MIT reveals much about how that subfield evolved. 相似文献
80.
Komornikov V. A. Timakov I. S. Zajnullin O. B. Grebenev V. V. Makarova I. P. Selezneva E. V. Ksenofontov D. A. 《Crystallography Reports》2019,64(6):984-990
Crystallography Reports - The phase equilibria in the CsHSO4–CsH2PO4–NH4H2PO4–H2O four-component aqueous salt system have been studied. The crystallization ranges and solubilities... 相似文献