排序方式: 共有41条查询结果,搜索用时 390 毫秒
31.
以4-乙基苯胺1为原料,经Sandmeyer反应得5-乙基靛红2;2经水合肼还原得到5-乙基-2-吲哚酮3;N,N-二甲基甲酰胺与三氯氧磷先形成Vilsmeier-Haack试剂,再与化合物3反应,合成2-氯-5-乙基-3-乙酰吲哚4;以丙酮为溶剂,对化合物4烃基化,以78.5%-95.6%的收率得到N-取代-2-氯-5-乙基-3-乙酰吲哚5a-5e。其中化合物4、5a-5e均未见文献报道,它们的结构均通过红外光谱、核磁共振氢谱(碳谱),质谱等确认。 相似文献
32.
Cyclization of 1-phenylpropane-1,2-dione monoarylhydrazones under Vilsmeier-Haack conditions gave 1-aryl-3-benzoyl-4-formylpyrazoles which were converted to 1-aryl-3-benzoyl-4-carboxypyrazoles using potassium permanganate in aqueous pyridine medium. 相似文献
33.
V. I. Terenin M. A. Butkevich A. S. Ivanov N. A. Tselischeva E. V. Kabanova 《Chemistry of Heterocyclic Compounds》2008,44(1):73-77
The formylation of pyrrolo[1,2-a]pyrazines containing alkyl, aryl, or hetaryl substituents in positions 1 and 6 of the heterocycle
has been studied. It has been shown that formylation of 1-phenyl-and 1-(2 thienyl)pyrrolo[1,2-a]pyrazine occurs selectively
at the α-position of the pyrrole ring. In all of the remaining examples the reaction course depends on substituent, reagent
ratio, and reaction time.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 88–93, January, 2008. 相似文献
34.
Yi Luo Ping Zhong~* Xiao Hong Zhang Qiu Lian Lin Ye Na Chen College of Chemistry Materials Science Wenzhou University Wenzhou China 《中国化学快报》2008,19(4):383-386
Two species of N-arylpyrazoles containing active amino group were synthesized.And formylations of N-arylpyazoles containing amino in different position of pyrazole rings using Vilsmeier-Haack reaction gave a series of useful pyrazole intermediates.The important features of this protocol were cheap materials,easy process,mild reaction conditions and good yield of products. 相似文献
35.
36.
Novel 6-chloropyrazolo[3,4-b]pyridine-5-carbaldehydes 5 have been synthesized from the 4,5-dihydropyrazolo[3,4-b]pyridine-6-ones 4 via Vilsmeier-Haack reaction. Further treatment of carbaldehydes 5 with acetophenones 6 and hydrazine hydrate afforded chalcone analogues 7 and dipyrazolo[3,4-b:4′,3′-e]pyridines 8, respectively. 相似文献
37.
Marta M. Andrade 《Tetrahedron》2004,60(41):9235-9243
The direct O-formylation of two selectively protected sugar derivatives using the Vilsmeier-Haack (V-H) complex POCl3·DMF was studied. Primary O-TBDMS and O-TBDPS ethers of sucrose, the most common disaccharide, underwent regio and chemoselective O-formylation with this formylating agent. This conversion was also studied with a monosaccharide analogue. 相似文献
38.
A new Vilsmeier-type reaction is suggested for the synthesis of novel indocarbocyanine pH sensors, which are fluorescent when protonated but nonfluorescent upon proton abstraction. These sensors show significant ratiometric UV-visible as well as fluorescence spectral changes upon subtle variation of pHs with pKa values near neutral. 相似文献
39.
Paulson Mathew 《Tetrahedron letters》2005,46(3):475-478
α-Oxoketene-N,S-acetals, prepared by the reaction of alkyl glycinates with β-oxodithiocarboxylates followed by alkylation, underwent cyclization in the presence of the Vilsmeier reagent to afford alkyl 3-aryl-4-formyl-5-(alkylsulfanyl)-1H-pyrrole-2-carboxylates in excellent yields. When the reaction was extended to β-oxodithiocarboxylates derived from deoxyanisoin, 3,4-diarylpyrrole-2-carboxylates, the key intermediates in the synthesis of lukianol A and lamellarin Q were formed. 相似文献
40.
V. Nithyadevi S. P. Rajendran 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1849-1862
The compounds selenolo(2,3-b)quinoline-2-carboxylic ethyl esters were synthesized in good yields by the reaction of 3-(2-chloro-3-quinolyl)acrylic ethyl esters, with the nucleophilic reagent sodium diselenide in ethanol medium under a nitrogen atmosphere. Cytogenetic studies on human blood leucocytes in vitro were evaluated for some of the synthesized compounds. Most of the synthesized compounds were tested for their antibacterial and antifungal activities. 相似文献