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91.
两个单桥连的双环戊二烯(C5Me4H) E(C5Me4H)(E=C6H4,(C6H4)2)分别与Re2(CO)10在均三甲苯中加热回流,得到了2个双核配合物(E)[(η5-C5Me4) Re(CO)3]2(E=C6H4(1),(C6H4)2(2))。通过元素分析、红外光谱、核磁共振氢谱和碳谱对配合物1和2的结构进行了表征,用X射线单晶衍射分析测定了配合物的结构。同时对2个配合物在芳香族化合物Friedel-Crafts酰基化反应中的催化活性进行了研究。 相似文献
92.
研究了一种基于Friedel-Crafts亲电取代的新型缩聚反应,反应基团是氮原子的苯对位氢原子和芴醇上的羟基,氮原子的富电子效应活化了苯对位氢原子的亲电取代能力,同时芴醇(似三苯甲醇结构)是高活性的烷基化试剂,使得小分子亲电取代反应可扩展为高分子缩聚反应.探索了两种缩合途径,"A-A,B-B"型共缩聚和"A-B"型自缩聚.4,4′-双(苯基-对甲苯基氨基)联苯(TPD)与芴醇共缩聚,得到数均分子量为1·5×104~2·0×104的共聚物,而芴醇的自缩聚,可得到单分散、立体环状结构的3聚体. 相似文献
93.
In fluorous biphase system, hafnium(IV) bis(perfluorooctanesulfonyl)amide complex (Hf[N(SO2C8F17)2]4) was found to be a highly reactive and recyclable Lewis acid catalyst for Friedel-Crafts acylation and Prins reaction at significantly low catalyst loadings (≤1 mol%). In these reactions, Hf[N(SO2C8F17)2]4 is selectively soluble in the lower fluorous phase and can be recovered simply by phase separation. Furthermore, the catalyst can be reused without decrease of activity. 相似文献
94.
Pijus Kumar Mandal 《Tetrahedron letters》2005,46(21):3715-3718
Under acidic conditions, the N(1)-C(4) bond of 4-(4′-hydroxyphenyl)-azetidine-2-ones are cleaved with the formation of a stabilized benzylic carbocation intermediates. The intermediates were reduced by silanes or participated in intramolecular or intermolecular Friedel-Crafts reactions to produce tyrosine mimetics. 相似文献
95.
Ko Hoon Kim 《Tetrahedron letters》2009,50(11):1249-3518
3,4-Disubstituted 2(1H)-quinolinones were synthesized starting from the Baylis-Hillman adducts via the following sequential processes: (i) hydrolysis of the Baylis-Hillman adduct to acid, (ii) EDC coupling with anilines, (iii) H2SO4-assisted intramolecular Friedel-Crafts cyclization, and the final (iv) DBU-mediated isomerization. 相似文献
96.
A catalytic, green and practical method for Friedel-Crafts hydroxyalkylation of mucohalic acid has been accomplished. Reaction of mucohalic acids with various electron-rich aromatic compounds in the presence of catalytic (1 mol % to 10 mol %) In(OTf)3 or Brönsted acid, such as H2SO4 in acetic acid provides γ-aryl γ-butenolides in moderate to excellent yield. 相似文献
97.
A novel porous aromatic framework, PAF-8, derived from tetraphenylsilane as basic building unit, was successfully synthesized via Friedel–Crafts alkylation reaction. This PAF material had high thermal stability as well as high surface area(785 m~2g~(-1)) calculated from the Brunauer–Emmett–Teller(BET)model. Meanwhile, PAF-8 possessed high performances in gas sorption and especially for CO_2 separation. 相似文献
98.
99.
Keto esters 8, 4-arylcarbonyl-3-methoxycarbonyl-2-phenylfurans, potential precursors of the synthesis of furofuran lignans, were obtained from dimethyl 2-phenylfuran-3,4-dicarboxylate 2.Diester 2 was selectively hydrolyzed to monoacid 6 followed by converting to its acid chloride 7.Friedel-Crafts acylation reactions of 7 with aromatic compounds afforded keto esters 8.The geometric structures of 8 and its precursors were elucidated and verified by NMR spectra. 相似文献
100.
Masahiro Mizuno Atsushi Inagaki Makoto Yamashita Norie Soma Yoshiharu Maeda Hiroshi Nakatani 《Tetrahedron》2006,62(17):4065-4070
A practical method for the preparation of TAK-603, an antirheumatic drug, has been developed. As a result of optimizing the Friedel-Crafts reaction in the presence of SnCl4/POCl3, 2-aminobenzophenone skeleton, the key intermediate of TAK-603, was formed with good yield. The selective substitution reaction of 1,2,4-triazole was accomplished using 4-amino-1,2,4-triazole and deamination. 相似文献