Ring transformations of heterocyclic compounds.<b>XXII</b>. Pyrido[1,2-<i>a</i>]indolium salts from 2-methyl-3<i>H</i>-indoles by pyrylium mediated three carbon annelation
作者:Thomas Zimmermann、Lothar Hennig
DOI:10.1002/jhet.5570390203
日期:2002.3
The synthesis of pyrido[1,2-a]indolium perchlorates 8,11 from 2,4,6-triarylpyrylium perchlorates 1 and 2-methyl-3H-indoles 6,9 in the presence of a basic condensing agent (anhydrous sodium acetate, piperidine acetate, triethylamine/acetic acid, triethylamine) in ethanol by a 2,4-[C3+C2N] pyryliumringtransformation is reported. Spectroscopic data of the transformation products and their mode of formation
吡啶并合成[1,2一]吲哚鎓高氯酸盐-8,11-从2,4,6-三芳基高氯酸盐1和2-甲基-3- ħ -indoles 6,9在碱性缩合剂的存在下(无水醋酸钠报道了乙醇中乙酸哌啶,三乙胺/乙酸,三乙胺通过2,4- [C 3 + C 2 N]吡啶鎓环的转化。讨论了转化产物的光谱数据及其形成方式。
An eco-benign and high speed protocol for the synthesis of 2-aroyl-3,5-diarylfuran derivatives using Teflon-supported iodine
AbstractA new, practical, and convenientapproach has been established for the expeditious synthesis of bioactive 2-aroyl-3,5-diarylfurans in excellent yields using a iodine-impregnated Teflon by a microwave-promoted process. The products are isolated without tedious aqueous work-up in high purity. The microwave accelerated the reaction and renders the whole synthesis into a truly eco-friendly protocol
Abstract Ringcontraction of 2,4,6-triarylpyrylium perchlorates by use of sodium nitrite mediated by ionic liquid has been used as a new, direct, and environmentally benign method for synthesis of bioactive 2-aroylfuran and novel 3,5-diaroyl-4-arylisoxazole derivatives in excellent yields. The versatility of the approach enables rapid and simple access to these pharmaceutically important compounds
In this work, for the first time, task‐specific ionic liquid, 1‐n‐butyl‐3‐methylimidazolium borohydride ([bmim]BH4), was used as the medium as well as reagent for the regiospecific reduction of triarylpyrylium perchlorates to provide aromatic dienones as only product. The [bmim]BH4 having a reactive anion also could promote the desired reaction thereby reducing the reaction times and improving the
Ring transformations of heterocyclic compounds.<b>XXI</b>. Diastereoselective built-up of an aroylcyclohexadiene moiety as second spiro-connected ring at spiroindolines by pyrylium ring transformation
作者:Thomas Zimmermann
DOI:10.1002/jhet.5570390202
日期:2002.3
cycloalkene or a heterocyclic system. These diastereoselective 2,5-[C4+C2] pyrylium ringtransformations are carried out in the presence of triethylamine/acetic acid in boiling ethanol to give the dispiroindolines 4 with a trans configuration of the more bulky substituents at the cyclohexadiene ring. By the same type of transformation the dispiro compounds 7/10 with an additional fused benzene ring are obtained
2,4,6-三芳基吡啶鎓高氯酸盐1与由相应的甲基吲哚盐2原位生成的亚甲基二氢吲哚3 反应,该亚甲基二氢吲哚盐3与环烷烃,苯甲酰化环烯烃或杂环系统螺旋稠合。这些非对映选择性的2,5- [C 4 + C 2 ]吡喃鎓环转化是在三乙胺/乙酸的存在下于沸腾的乙醇中进行的,以得到在环己二烯环上具有更大体积取代基的反式构型的二螺二吲哚啉4。通过相同类型的转化,双螺化合物7/10从吡喃鎓盐1a和6/9(苯并稠合的3的类似物)获得带有额外的稠合苯环的苯并稠合类似物。讨论了转化产物的光谱数据及其形成方式。