Efficient Synthetic Approach to Substituted Benzo[<i>b</i>]furans and Benzo[<i>b</i>]thiophenes by Iodine-Promoted Cyclization of Enaminones
作者:Ehecatl Labarrios、Alberto Jerezano、Fabiola Jiménez、María del Carmen Cruz、Francisco Delgado、L. Gerardo Zepeda、Joaquín Tamariz
DOI:10.1002/jhet.1686
日期:2014.7
An efficient synthetic approach to the substituted benzo[b]furan and benzo[b]thiophene scaffolds by iodine‐mediated cyclization of the corresponding enaminones is described. This protocol was applied to a large series of these latter precursors to afford the respective benzoheterocycles substituted at the C‐2 position by a carbonyl group functionality. A study of the factors that control this process
描述了一种通过碘介导的相应烯胺酮环化取代苯并[ b ]呋喃和苯并[ b ]噻吩骨架的有效合成方法。该方案适用于大量的这些后者的前体,以提供各自的苯并杂环在C-2位置被羰基官能团取代。对控制该过程的因素的研究表明,反应性取决于芳氧基羰基和芳硫羰基部分的芳环中电子给体基团的存在。
Shifted Selectivity in Protonation Enables the Mild Deuteration of Arenes Through Catalytic Amounts of Bronsted Acids in Deuterated Methanol
作者:Oliver Fischer、Anja Hubert、Markus R. Heinrich
DOI:10.1021/acs.joc.0c01604
日期:2020.9.18
effect” of the solvent methanol, deuterations of electron-rich aromatic systems can be carried out under mild acid catalysis and thus under far milder conditions than known so far. The exceptional functional group tolerance observed under the optimized conditions, which even includes highly acid-labile groups, results from a hitherto unexploited shifted selectivity in protonation, and enabled simple
A New Synthetic Route of 2-Aroyl- and 2-Benzyl-Benzofurans and their Application in the Total Synthesis of a Metabolite Isolated from Dorstenia gigas
作者:Christian Correa、María del Carmen Cruz、Fabiola Jiménez、L. Gerardo Zepeda、Joaquín Tamariz
DOI:10.1071/ch08243
日期:——
regioselective and short synthesis of 2-aroylbenzofurans 2a–h. The Wolff–Kishner reduction of the latter yielded a series of substituted 2-benzylbenzofurans 3a–h. This methodology was applied in the first totalsynthesis of the metabolite 2-(4-hydroxybenzyl)-6-methoxybenzofuran 1, which was isolated from the tropical plant Dorstenia gigas, and obtained through a six-step route and in a 24% overall yield
Various aromatic selenocyanates were successfully delivered in moderate to excellent yields (up to 99 % yield) via direct selenocyanation of arenes/heterocyclic arenes with electrophilic selenocyanating reagents using Mechanochemistry. This protocol exhibits the advantages of operationally simple, environmentally friendly and time-economy.
Provided is a method for the preparation of a deuterated or tritiated aromatic compound via deuteration or tritiation of an aromatic starting compound which comprises an aromatic ring or a fused aromatic ring system which may be carbocyclic or hetercyclic and which carries at least one hydrogen atom directly bonded to a carbon ring atom of an aromatic ring, said method comprising:
a) providing a liquid composition wherein the aromatic starting compound is dissolved or dispersed in a deuterated or tritiated solvent which is not water, or in a solvent system comprising at least one deuterated or tritiated solvent which is not water; and
b) replacing at least one hydrogen atom directly bonded to a carbon ring atom of an aromatic ring comprised by the aromatic starting compound with deuterium or tritium via the transfer of at least one deuterium of tritium atom from the deuterated or tritiated solvent to the aromatic starting compound dissolved or dispersed in the liquid composition in the presence of an acid,
to convert the aromatic starting compound to a deuterated or tritiated aromatic compound which comprises an aromatic ring or a fused aromatic ring system which may be carbocyclic or hetercyclic and which carries at least one deuterium or tritium atom directly bonded to a carbon ring atom of an aromatic ring.
本发明提供了一种通过对芳香族起始化合物进行氚化或氚化来制备氚化或三氚化芳香族化合物的方法,所述芳香族起始化合物包括一个芳香环或一个可为碳环或杂环的融合芳香环系统,且至少携带一个与芳香环的碳环原子直接键合的氢原子,所述方法包括
a) 提供液体组合物,其中芳香族起始化合物溶解或分散在非水的氚代或三氚代溶剂中,或溶解或分散在包含至少一种非水的氚代或三氚代溶剂的溶剂体系中;以及
b) 在酸存在的情况下,通过将至少一个氘原子或氚原子从氚化或氚化溶剂转移到溶解或分散在液体组合物中的芳香族起始化合物,用氘原子或氚原子取代与芳香族起始化合物所包含的芳香环的碳环原子直接结合的至少一个氢原子、
将芳香族起始化合物转化为氚化或氚化芳香族化合物,该芳香族化合物包含一个芳香环或一个融合芳香环系统,该芳香环系统可以是碳环或杂环,并携带至少一个直接键合到芳香环碳环原子上的氘或氚原子。