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排序方式: 共有270条查询结果,搜索用时 15 毫秒
1.
Mi Jung Lee 《Tetrahedron letters》2006,47(8):1355-1358
A new and regioselective [4+2] benzannulation protocol toward polysubstituted benzenes was developed. Nitroalkane derivative, which was prepared from Baylis-Hillman adduct, served as the four-carbon unit and Michael acceptor as a two-carbon unit. 相似文献
2.
Jean-Marc Kern Jean-Pierre Sauvage Gerard Bidan Bernadette Divisia-Blohorn 《Journal of polymer science. Part A, Polymer chemistry》2003,41(22):3470-3477
This article provides an overview of the fundamental principles of the synthesis of metallocatenanes and metallorotaxanes. It also describes the synthesis and properties of electronic conducting polymers—polypyrrole and polythiophene—built around metallocatenanes and metallorotaxanes. The particular properties of this new class of polymers, including the possibility of transmetallation reactions being performed with them and the observation of electronic coupling between the metal centers and the conducting matrix, are discussed. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3470–3477, 2003 相似文献
3.
Reaction of 2-(vinyloxy)ethylisothiocyanate with unsaturated carbanions generated in situ from propargyl ethers and amines when treated with superbases, after S-alkylation and cyclization of the adducts in the presence of CuBr, leads to the previously unknown 2,3,5-substituted 1-[2-(vinyloxy)ethyl]pyrroles. 相似文献
4.
Mi-Young Song En-Young Kim Kyung Il Kim Hong-Seok Kim Chang-Hee Lee 《Tetrahedron letters》2004,45(2):299-301
Furans, thiazoles, fluorene or thiophene incorporated calix[4]pyrrole analogues were synthesized and characterized. The synthesis was achieved by utilization of various building blocks such as 7, 13, 14, 18 and 21. Acid catalyzed condensation of those building blocks with acetone or meso-disubstituted dipyrromethanes afforded desired macrocycles. 相似文献
5.
Mi Jung Lee 《Tetrahedron》2006,62(13):3128-3136
A new and regioselective [4+2] benzannulation protocol toward polysubstituted benzenes was developed. A nitroalkane derivative, which was prepared from Baylis-Hillman adduct, served as the four-carbon unit and a Michael acceptor as a two-carbon unit. Vinyltriphenylphosphonium salt could also be used as a Michael acceptor efficiently. 相似文献
6.
Da Yeon Park 《Tetrahedron letters》2006,47(37):6641-6645
Polysubstituted benzene derivatives were synthesized starting from the Baylis-Hillman adducts via the sequential introduction of primary nitroalkane at the primary position, Michael addition to β-branched Michael acceptor, aldol condensation, elimination of nitrous acid, and the final aromatization process. 相似文献
7.
A novel oxidation-ring-contraction reaction took place when 4-substituted Hantzsch 1,4-dihydropyridines were treated with Oxone. This reaction pattern provided a convenient method for the synthesis of polysubstituted furans. 相似文献
8.
N,N′-双吡咯的合成及其邻位基团效应 总被引:1,自引:0,他引:1
2,2-联吡咯是某些天然存在的活性吡咯化合物中关键组成,关于手性联吡咯的研究己有详细的综述报道。近年发现,某些含N-取代氨基的空间阻碍吡咯有明显的生理活性和可贵的药理性质。N,N′-联吡咯中N-N键,很容易发生均裂反应而生成游离基,后 相似文献
9.
本文报道用环加成-芳构化串连反应制备多取代芳香族化合物的方法。将1-氯-2-卤-3-苯硒基-1,3-丁二烯(5)与丁炔二酸二甲酯进行Diels-Alder反应时,能直接生成多取代的芳香族化合物4-苯硒基-5-卤代邻苯二甲酸二甲酯(4)。若用2-卤素-3-苯硒基-1,3-丁二烯(1)与丁炔二酸二甲酯进行Diels-Alder反应,只得到正常的加成产物4-苯硒基-5-卤素-1,4-环己二烯-1,2-二甲酸二甲酯(3),需再用DDQ处理,才得到多取代芳香族化合物(4)。 相似文献
10.
Cathodic reduction of phenacyl bromides N-acyl hydrazones lead to dimeric 1,4-diaryl-1,4-butanedione di-N-acylhydrazones, which give the corresponding 1-N-acylamino-2,5-diarylpyrroles in good yields. 相似文献