Pyridinium Halides and Their Mixtures as Inhibitors of Steel Corrosion in Sulfuric Acid Solutions
作者:R. I. Yurchenko、S. V. Ivashchenko、T. N. Pilipenko、I. S. Pogrebova
DOI:10.1007/s11167-005-0329-5
日期:2005.3
Mixtures of 1-acylmethylpyridinium halides with equimolar amounts of pyridinium halides were prepared by the Ortoleva-King reaction. The inhibiting effect of various pyridinium halides and their mixtures on corrosion of steel in sulfuric acid solutions was studied.
Enantioselective Synthesis of 3-Allylindolizines via Sequential Rh-Catalyzed Asymmetric Allylation and Tschitschibabin Reaction
作者:Ke Li、Changkun Li
DOI:10.1021/acs.orglett.0c03383
日期:2020.12.18
The first highly regio- and enantioselectivesynthesis of 3-allylindolizines has been developed by the sequential Rh-catalyzed asymmetric allylation and Tschitschibabin reaction. Above the 20:1 branch/linear ratio, up to a 96% yield and 99% ee could be obtained with the help of tert-butyl-substituted chiral bisoxazolinephosphine ligand. In situ generated highly nucleophilic 2-alkylpyridinium ylides
Studies on furan derivatives. VII. Reactions of .ALPHA.-(2-furyl)-.BETA.-(5-nitro-2-furyl)ethynyl.
作者:AKIRA TANAKA、TOSHINAO USUI
DOI:10.1248/cpb.27.3078
日期:——
Addition of amines to α-(2-furyl)-β-(5-nitro-2-furyl) ethynyl (I) gave N-substituted α-(2-furyl)-β-(5-nitro-2-furyl) vinylamines. Bromination of I gave stereoisomers which were identified as E- and Z-forms, judging from their ultraviolet absorption spectra. The reaction of I with N-substituted pyridinium ylides was not uniform. Only the common indolizines, namely 3-substituted 1-(5-nitro-2-furyl)-2-(2-furyl) indolizines, were obtained by reaction in dioxane, whereas 3-substituted 1-(4-alkylated 5-nitro-2-furyl)-2-(2-furyl)-indolizines were isolated by reaction in dimethylformamide, together with the common indolizines.
在 α-(2-呋喃基)-β-(5-硝基-2-呋喃基)乙炔基(I)上添加胺,可得到 N-取代的 α-(2-呋喃基)-β-(5-硝基-2-呋喃基)乙烯基胺。I 的溴化反应产生了立体异构体,根据它们的紫外吸收光谱,可确定为 E 型和 Z 型。I 与 N-取代的吡啶鎓酰化物的反应并不一致。在二噁烷中反应只得到了常见的吲嗪类化合物,即 3-取代的 1-(5-硝基-2-呋喃基)-2-(2-呋喃基)吲嗪类化合物,而在二甲基甲酰胺中反应则分离出了 3-取代的 1-(4-烷基化的 5-硝基-2-呋喃基)-2-(2-呋喃基)-吲嗪类化合物以及常见的吲嗪类化合物。
Tschitschibabin, Chemische Berichte, 1927, vol. 60, p. 1614