Synthesis of 2,3-Disubstituted Benzo[<i>b</i>]thiophenes via Palladium-Catalyzed Coupling and Electrophilic Cyclization of Terminal Acetylenes
作者:Dawei Yue、Richard C. Larock
DOI:10.1021/jo011016q
日期:2002.3.1
alkyl-substituted terminal acetylenes undergo this coupling and cyclization to produce excellent yields of benzo[b]thiophenes. (Trimethylsilyl)acetylene also undergoes this coupling/cyclization process with I(2), NBS, and the sulfur and selenium electrophiles to afford the corresponding 2-(trimethylsilyl)benzo[b]thiophenes. However, cyclization of the silyl-containing thioanisole using Br(2) affords
AgNO2-catalyzed radicalcyclization of 2-alkynylanisoles (or 2-alkynylthioanisoles), Se powder, and arylboronic acids. This method enables the construction of a benzofuran (benzothiophene) ring, two C-Se bonds, and a C-O(S) bond as well as the cleavage of a C-O(S) bond in a single step. Preliminary mechanistic studies imply that the AgNO2-catalyzed cyclization proceeds via an aryl selenium radical intermediate
Synthesis of benzo[b]thiophenes by electrophilic cyclization
作者:Richard C Larock、Dawei Yue
DOI:10.1016/s0040-4039(01)01149-2
日期:2001.8
2,3-Disubstitutedbenzo[b]thiophenes are readily prepared in excellent yields under very mild reaction conditions by the Pd/Cu-catalyzed cross-coupling of commercially available o-iodothioanisole and terminal alkynes, followed by electrophilic cyclization by I2, Br2, NBS, p-O2NC6H4SCl or PhSeCl.
2,3-二取代的苯并[ b ]噻吩在很温和的反应条件下,可通过Pd / Cu催化的可商购的邻碘碘苯甲醚和末端炔烃的交叉偶联,然后通过I 2,Br 2,NBS,p -O 2 NC 6 H 4 SCl或PhSeCl。
Trichloroisocyanuric Acid (TCCA): A Suitable Reagent for the Synthesis of Selanyl‐benzo[
<i>b</i>
]chalcogenophenes
作者:Gustavo B. Blödorn、Luis Fernando B. Duarte、Juliano A. Roehrs、Márcio S. Silva、José S. S. Neto、Diego Alves
DOI:10.1002/ejoc.202200775
日期:2022.10.26
A new protocol for the synthesis of different 3-organyl-benzo[b]chalcogenophenes was developed through the reaction of diorganyl diselenides with trichloroisocyanuric acid (TCCA) in ethanol. Under the optimized reaction conditions, a range of benzo[b]furans, benzo[b]thiophenes and benzo[b]selenophenes were synthesized in good to excellent yields using mild reaction conditions.
通过二有机基二硒化物与三氯异氰脲酸 (TCCA) 在乙醇中的反应,开发了一种合成不同 3-有机基苯并[ b ]硫族酚的新方案。在优化的反应条件下,一系列苯并[ b ]呋喃、苯并[ b ]噻吩和苯并[ b ]硒吩类化合物在温和的反应条件下以良好至优异的收率合成。