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41.
Dr. Xisen Hou Prof. Chenfeng Ke Dr. Yu Zhou Dr. Zhuang Xie Dr. Ahmed Alngadh Dr. Denis T. Keane Dr. Majed S. Nassar Dr. Youssry Y. Botros Prof. Chad A. Mirkin Prof. J. Fraser Stoddart 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(35):12301-12306
Covalent and supramolecular polymerizations, both of which offer their own unique advantages, have emerged as popular strategies for making artificial materials. Herein, we describe a concurrent covalent and supramolecular polymerization strategy—namely, one which utilizes 1) a bis‐azide‐functionalized diazaperopyrenium dication that undergoes polymeriation covalently with a bis‐alkyne‐functionalized biphenyl derivative in one dimension as a result of a rapid and efficient β‐cyclodextrin(CD)‐accelerated, cucurbit[6]uril(CB)‐templated azide–alkyne cycloaddition, while 2) the aromatic core of the dication is able to dimerize in a criss‐cross fashion by dint of π–π interactions, enabling simultaneous supramolecular assembly, resulting in an extended polymer network in an orthogonal dimension. 相似文献
42.
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
43.
Tiesheng Li Wenjian Xu Caiqin Tang Min Zhang Yangjie Wu Tokuji Miyashita 《Journal of Polymer Science.Polymer Physics》2012,50(2):139-147
A new series of copolymer poly(N‐hexadecylmeth acrylamide‐co‐bis(anthracen‐9‐ylmethyl) 2‐allylmalonate) [poly(HDMA‐co‐DAnMAMA)]s containing swallow‐tailed double anthracenyl groups and long alkyl group are designed and synthesized. The main route of the photochemical reaction of the p(HDMA‐DAnMAMA)copolymer Langmuir–Blodgett (LB) films is dimerization reaction between the anthracenyl groups under the irradiation of both 365 and 248 nm for limiting irradiation time, resulting to a fine negative‐tone pattern. On the other hand, the anthracenyl groups act just as photodecomposition group under 248 nm for longer irradiation time, resulting to a fine positive‐tone pattern. Consequently, positive‐tone and negative‐tone pattern are obtained by choosing not only a suitable irradiation light wavelength, but the irradiation time at 248 nm. Moreover, it is found that the exposed and unexposed regions of copolymer LB films irradiated at 248 nm have solubility differentiation in gold etchant (I2/NH4I/C2H5OH/H2O), that is to say, the gold photopatterns with the maximal resolution of the used mask can be obtained easily without any development process. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 50: 139–147, 2012 相似文献
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《应用有机金属化学》2017,31(9)
A β‐diketimine ligand with vinylidene substitution at γ‐carbon, CH2C(CH3CNAr)2 (Ar = 2,6‐diisopropylphenyl) ( L 2 ), was synthesized by treating β‐diketimine H2C(CH3CNAr)2 with n ‐BuLi followed by paraformaldehyde. L 2 formed the homobimetallic ether‐bridged β‐diketiminate complex [O{(CH2‐β‐diketiminate)Pd(OAc)}2] ( 1 ) with (PdOAc)2. It also gave complexes [L2PdCl2] ( 2 ) and [L2NiBr2] ( 3 ) when treated with PdCl2(CH3CN)2 and NiBr2(dimethoxyethane), respectively. All the compounds were characterized using 1H/13C NMR spectroscopy and single‐crystal X‐ray diffraction studies. The catalytic activity of Pd and Ni complexes 1 , 2 and 3 was explored in Heck coupling and alkyne trimerization reactions and it was found that they are very good catalysts. The results are reported in detail. 相似文献
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47.
Bernhard Wölfl Dr. Guillaume Mata Prof. Alois Fürstner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(1):255-259
The macrocyclic core of the cytotoxic marine natural product callyspongiolide ( 1 ) was forged by ring-closing alkyne metathesis (RCAM) of an ynoate precursor using a molybdenum alkylidyne complex endowed with triarylsilanolate ligands as the catalyst. This result is remarkable in view of the failed attempts documented in the literature at converting electron deficient alkynes with the aid of more classical catalysts. The subsequent Z-selective semi-reduction of the resulting cycloalkyne by hydrogenation over nickel boride required careful optimization in order to minimize overreduction and competing dehalogenation of the compound's alkenyl iodide terminus as needed for final attachment of the side chain of 1 by Sonogashira coupling. The required cyclization precursor itself was prepared via Kocienski olefination. 相似文献
48.
《化学:亚洲杂志》2017,12(6):643-647
A fully conjugated system 4 consisting of two 2‐aza‐21‐carbaporphyrin (NCP) subunits bridged by dipyrrin was synthesized by a highly selective condensation of 3‐pyrrole‐NCP 2 with aryl aldehydes. The free base 4 as well as its silver(III) complex 5 exhibited flexibility of the bridge allowing synergetic binding of AgI, thus leading to a mixed‐valence tetraporphyrinic assembly consisting of eight silver atoms which was characterized both in the solid state and in solution. Binding of chiral acid by 4 and 5 was shown by observation of an induced optical activity of the adducts. 相似文献
49.
50.
Dr. Wenlong Yang Dr. Jorge H. S. K. Monteiro Prof. Ana de Bettencourt-Dias Prof. Vincent J. Catalano Prof. Wesley A. Chalifoux 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(6):1441-1445
This work explores the syntheses, structures, photophysical properties, and photostability of benzodipyrenes (BDPs). BDPs were synthesized through an InCl3-AgNTf2-catalyzed, four-fold alkyne benzannulation reaction. The structures of BDP 4 a and its corresponding endoperoxide product were unambiguously confirmed by X-ray crystallography. The BDPs reported here can also be recognized as peri- and cata-benzannulated pentacenes with a non-functionalized central ring. Unlike the previous reported pentacene-based polycyclic aromatic hydrocarbons, the absorbances of the BDPs were blueshifted by ca. 40 nm relative to pentacene, even after extension of π-conjugation. The newly synthesized BDP products exhibit relatively good stability with half-lives as high as 4612 min in THF. 相似文献