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991.
Pengcheng Qian 《合成通讯》2013,43(21):3242-3250
An efficient Rh-catalyzed dimerization of diaryl acetylenes was achieved in the presence of Wilkinson catalyst, AgF2, and 1.5 equivalent of PhMgBr in toluene, providing the 1,2,3-triaryl naphthalene derivatives in moderate to good yields. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications to view the free supplemental file. 相似文献
992.
Stacey M. Frumm Zi Peng Fan Kenneth N. Ross Jeremy R. Duvall Supriya Gupta Lynn VerPlank Byung-Chul Suh Edward Holson Florence F. Wagner William B. Smith Ronald M. Paranal Christopher F. Bassil Jun Qi Giovanni Roti Andrew L. Kung James E. Bradner Nicola Tolliday Kimberly Stegmaier 《Chemistry & biology》2013,20(5):713-725
993.
994.
Yang Min Dr. Chuandong Dou Prof. Hongkun Tian Prof. Jun Liu Prof. Lixiang Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(13):4364-4372
The B←N unit has a large dipole and it is isoelectronic to C−C moiety with no dipole. Incorporating B←N units into π-conjugated system is a powerful strategy to design organic small molecules and polymers with intriguing opto-electronic properties and excellent opto-electronic device performance. However, it is unclear how the B←N unit affects electronic structures and opto-electronic properties of large π-conjugated molecules. In this work, to address this question, we developed three dibenzo-azaacene molecules in which two B←N units were introduced at different positions. Although the dibenzo-azaacene skeleton is fully π-conjugated, the effect of B←N unit on the electronic structures of the adjacent rings is much stronger than that of the distant rings. As a result, the three molecules with isomerized B←N incorporation patterns possess different electronic structures and exhibit tunable opto-electronic properties. Among the three molecules, the centrosymmetrical molecule exhibits higher LUMO/HOMO energy levels than those of the two axisymmetrical molecules. When used as the active layer in organic field-effect transistors (OFETs), while the two axisymmetrical molecules show unipolar electron transporting property, the centrosymmetrical molecule exhibits ambipolar hole and electron transporting behavior. This work not only deepens our understanding on organoboron π-conjugated molecules, but also indicates a new strategy to tune opto-electronic properties of organic semiconductors for excellent device performance. 相似文献
995.
2N+1-soliton solutions of Boussinesq-Burgers equation are obtained by using the Hi-rota bilinear derivative method and the perturbation technique. Further, we give the graphs of corresponding three-and five-soliton solutions. 相似文献
996.
Thioxo/dithioxo-naphthalimide is a class of rarely visited fluorophore, first synthesized in 1999. Facile chemistry was devised to achieve mono or dual thionation of the two carbonyl groups of 1,8-naphthalimide. Thionation effectively shifts absorption maximum to longer spectral wavelength, significantly increase absorption coefficients, and dramatically enhances intersystem crossing efficiency with respect to their oxo-analogues. They were first explored as potent photocleavers to induce DNA strand break and novel photosensitizers for photodynamic therapies. In recent years, the unique chemistry of thioxo groups has been harnessed to achieve new applications, such as fluorescent sensors for heave metal ions. These unique photochemical and photophysical characteristics revitalize them intriguing functional molecules to investigate. In this short review, we wish to revisit their first discovery, facile synthesis, and the endeavors on the use of thioxo/dithioxo-naphthalimides for novel chemical and biomedical applications. 相似文献
997.
998.
999.
Qian Yan 《Numerical Functional Analysis & Optimization》2013,34(13):1351-1373
AbstractThe aim of this paper is to introduce the generalized viscosity implicit rules of one asymptotically nonexpansive mapping in the intermediate sense in Hilbert spaces. We obtain some strong convergence theorems under certain assumptions imposed on the parameters. We also give a numerical example to support our main results. The results obtained in this paper improve and extend many recent ones in this culture. 相似文献
1000.
A new synthetic method for methyl 2-benzyloxylphenylacetate, a key intermediate of a new type of fungicides, had been found, which has only 3 steps. The 80% yield of the new method is a major improvement over the 30% 6-step-process reported by the literature. 相似文献