共查询到20条相似文献,搜索用时 10 毫秒
1.
Andrew A. Tolmachev Alexander A. Yurchenko Ernest S. Kozlov Anatoliy S. Merkulov Marina G. Semenova Aleksander M. Pinchuk 《Heteroatom Chemistry》1995,6(5):419-432
The reaction of phosphorus(III) halides with imidazo[1,2-a]pyridines in the presence of bases leads to the formation of 3-phosphorylated imidazo[1,2-a]pyridines. The reaction proceeds in high yield and requires no catalysts. In the compounds obtained, in contrast to phosphorylated indolizines, the phosphorus–heterocycle bond is stable and not cleaved by dry hydrogen chloride, alcohols, or water. Imidazo[1,2-a]pyridines with the phosphinic and phosphinous groups can be alkylated both at the phosphorus and at the nitrogen atom of the heterocycle, the alkylation direction being dependent on the strength of the alkylation reagent used. © 1995 John Wiley & Sons, Inc. 相似文献
2.
Sokolov V. B. Aksinenko A. Yu. Epishina T. A. Goreva T. V. 《Russian Chemical Bulletin》2009,58(3):631-633
3-Fluoro-2-trifluoromethylimidazo[1,2-a]pyridines were obtained by reactions of hexafluoroacetone 2-pyridylimines with trimethyl phosphite and studied in reactions
with sodium methoxide. This gave the corresponding 3-methoxy-2-trifluoromethylimidazo[1,2-a]pyridines. 相似文献
3.
Ya. L. Gol'dfarb F. M. Stoyanovich M. A. Marakatkina G. I. Gorushkina 《Chemistry of Heterocyclic Compounds》1979,15(5):514-518
A number of 6-alkylthio(and sulfonyl)-substituted imidazo[1,2-a]pyridines were synthesized by the reaction of 5-alkylthio- and 5-alkylsulfonyl-2-aminopyridines with -bromoacetophenone and -chlorocyclohexanone in order to search for new compounds that have fungicidal activity. 5-Alkylthio-2-aminopyridines were obtained from the double salt of 5-mercapto-2-aminopyridine with SnCl2 and HCl by reaction with alkyl halides or tert-C4H9OH and 75% H2SO4. 5-tert-Butylthio-2-aminopyridine was oxidized by means of KMnO4 to 5-tert-butylsulfonyl-2-aminopyridine. A double salt was synthesized from 2-aminopyridine-5-sulfonic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 634–638, May, 1979. 相似文献
4.
3-Substituted imidazo[1,2-a]pyridines, imidazo[1,2-a]pyrimidines, and imidazo[1,2-c]pyrimidine were obtained regiospecifically in yields of 35-92% in one pot by reaction of 2-aminopyridines or 2-(or 4-)aminopyrimidines, respectively, with 1,2-bis(benzotriazolyl)-1,2-(dialkylamino)ethanes. 相似文献
5.
Yu. M. Volovenko V. V. Ivanov A. O. Pushechnikov 《Chemistry of Heterocyclic Compounds》2002,38(2):213-218
Bromination of 1-oxo(imino, amino)benzo[4,5]imidazo[1,2-a]pyridines gave the corresponding 2-bromo derivatives. Acylation using the Vilsmeier complex in acetic anhydride gave the N-formyl and N-acetyl derivatives. The reaction of the amine with the Vilsmeier complex, acetyl acetone, ethyl acetoacetate, and 2,5-dimethoxytetrahydrofuran occurs at the amino group. 相似文献
6.
7.
Lahboub Bouyazza Jean-Charles Lancelot Sylvain Rault Max Robba 《Journal of heterocyclic chemistry》1991,28(1):77-80
A-Acetoxypyrrolo[1,2a]quinolines 26-30 were synthesized by cyclization of 2-(1-pyrroly)phenylacetic acids 21-25 with acetic anhydride. The structures of the new compounds were determined by 1H-nmr spectroscopy. 相似文献
8.
2-Aminopyridines 1a-c and 1-aminoisoquinoline with 1-chloromethylbenzotriazole give 2-amino-1-[alpha-benzotriazol-1-ylmethyl]pyridinium chlorides 2a-c and 1-amino-2-(alpha-benzotriazol-1-ylmethyl)isoquinolinium++ + chloride 12, respectively. Compounds 2a-c and 12 react with aryl aldehydes 3a-h to afford imidazolo[1,2-a]pyridines 7a-k and imidazolo[2, 1-a]isoquinolines 13a,b in good yields. 相似文献
9.
E. Suloeva M. Yure E. Gudriniece M. Petrova A. Gutcaits 《Chemistry of Heterocyclic Compounds》2001,37(7):872-875
A series of 2-hydroxy-, 2-chloro-, and 2-(2-hydroxyethylamino)-6-aryl-4-polyfluoroalkyl-3-cyanopyridines has been synthesized. The latter react with phosphorus oxychloride to give fluorine containing 2,3-dihydroimidazo[1,2-a]pyridines. 相似文献
10.
YI Yangjie XU Leitao LIU Yuyang LI Mingfang ZHANG Lijuan YE Jiao HU Aixi 《高等学校化学研究》2023,39(2):318-324
Iodized salts are widely used as mediators to promote C—H functionalization. Solvents and additives have been described as significant roles in these reactions. However, the further electrochemical investigations have rarely been reported. Herein, a KI mediated electrochemical annulation between acetophenones and 2-amniopyridines was developed. We revealed the effect of acids and solvents by cyclic voltammetry(CV), differential pulse voltammetry(DPV), and square wave voltammetry(SWV). The oxidation of 2-aminopyridine is inhibited at the potential window with the addition of strong acids, and the lowest oxidation potential difference of KI was obtained by utilizing EtOH as solvent. The experimental studies also show that the mixture solvent of EtOH/DMSO(9/1, volume ratio) facilitates the electrochemical cyclization due to the solubility improvement of KI. CF3SO3H has been screened as the optimal acid. A range of Imidazo[1,2-a]- pyridines have been synthesized in yields of 42% to 96%. Electrochemical investigations present that the KI mediated electro- chemical reaction is probably solvent-dependence. 相似文献
11.
An efficient, metal-free method for the synthesis of 3-formyl imidazo[1,2-a]pyridines is reported. The method utilises commercially available substrates and features a broad substrate scope. The intermediate enamine was isolated and a plausible reaction mechanism proposed. 相似文献
12.
Ahmad Shaabani Fahimeh Rezazadeh Ebrahim Soleimani 《Monatshefte für Chemie / Chemical Monthly》2008,139(8):931-933
Ammonium chloride as a very inexpensive and readily available reagent efficiently catalyzes one-pot, three-component Groebke condensation reactions of aldehydes, isocyanides, and 2-aminopyridines or 2-aminopyrimidines in methanol to afford the corresponding
imidazo[1,2-a]pyridines in high yields at room temperature.
Correspondence: Ahmad Shaabani, Department of Chemistry, Shahid Beheshti University, PO Box 19396-4716, Tehran, Iran. 相似文献
13.
14.
Transformations of methyl 3-dimethylamino-2-(1-methoxycarbonyl-4-oxo-4H-pyrido[1,2-a]pyrazin-3-yl)acrylate with some cyanomethylenecarbonyl group containing compounds or cyanamide into imidazo-[1,2-a]pyridines, irmdazo[1,2-a]pyrimidines and 2-oxa-6a, 10c-diazaaceanthrylenes are described. 相似文献
15.
Imidazo[1,2-a]pyridines were obtained by direct reaction of acetophenone, propiophenone, and their furan analogs and ring-substituted derivatives with an equimolar amount of iodine and and excess 2-aminopyridine or its substituted derivatives. The effect of substituents in the ketones and 2-aminopyridine, the reagent molar ratios, the character of the solvents, and replacement of iodine by other halogenating agents on the course of the reaction and the yields of products was studied. The formation of 3-iodo- and 6-iodoimidazopyridines as side products was noted in the case of ketones that do not have electron-acceptor substituents in the ring. These and other iodo-substituted imidazopyridines were synthesized for chromatographic comparison.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1396–1405, October, 1976. 相似文献
16.
Summary. Reactions of sodium salts of 3-hydroxymethylene-2-alkanones with 2-cyanomethylbenzimidazole afforded benzimidazo[1,2-a]pyridines. Analogues reactions with 2-aminobenzimidazole and 5-aminopyrazoles afforded benzimidazo[1,2-c]pyrimidines and pyrazolo[1,5-a]pyrimidines.
Received December 12, 1999. Accepted (revised) February 12, 2000 相似文献
17.
A copper-catalyzed three-component reaction for the synthesis of sulfenylimidazo[1,2-a]pyridines using elemental sulfur as the sulfenylating agents has been developed. 相似文献
18.
Alexandra Basilio-Lopes Thiago Mendonça de Aquino Alexandre Mongeot Jean-Jacques Bourguignon Martine Schmitt 《Tetrahedron letters》2012,53(21):2583-2587
A convenient and general method of preparation of polyfunctionalized imidazo[1,2-a]pyridines is reported. This methodology involves activation of secondary amides leading to the formation of the corresponding amidines 9. Different activating reagents have been evaluated and the efficiency of PCl5 was illustrated with alkyl functionalized groups. 相似文献
19.
E. Suloeva M. Yure E. Gudriniece S. Belyakov M. Petrova I. Kalnite 《Chemistry of Heterocyclic Compounds》2001,37(3):329-337
Syntheses are reported for a series of 2-alkylamino-6-phenyl-4-trifluoromethylpyridines. The reaction of 3-cyano-2-(hydroxyalkylamino)-6-phenyl-4-trifluoromethylpyridines with thionyl chloride gave the corresponding 2-(chloroalkylamino)pyridines, 8-cyano-5-phenyl-7-trifluoromethyl-2,3-dihydro-imidazo[1,2-a]pyridines, and 9-cyano-6-phenyl-8-trifluoromethyl-2,3,4-trihydropyrido[1,2-a]-pyrimidines. X-ray diffraction structural analysis was used to study 8-cyano-5-phenyl-7-trifluoromethyl-2,3-dihydroimidazo[1,2-a]pyridine. 相似文献
20.
Condensation of aldehydes, isonitriles and 2‐aminopyridines in the presence of H3PMo12O40 affords different derivatives of 3‐aminoimidazo[1,2‐a]pyridine in good to excellent yields. 相似文献