Metal-free synthesis of 3-chalcogen benzo[b]furans via an iodine-mediated electrophilic cyclisation of 2-alkynylanisoles
作者:Mei Xu、Xiao-Hong Zhang、Ping Zhong
DOI:10.1016/j.tetlet.2011.10.045
日期:2011.12
An efficient and metal-free method was developed to synthesize 3-chalcogen benzo[b]furans via the iodine-mediatedelectrophilic cyclisation of 2-alkynylanisoles with disulfides or diselenides. In the presence of I2, various 3-sulfenylbenzofurans or 3-selenenylbenzofurans were obtained in moderate to high yields.
通过用二硫化物或二硒化物通过碘介导的2-炔基茴香醚的亲电亲电环化反应,开发了一种高效且无金属的方法来合成3-硫属元素苯并[ b ]呋喃。在I 2的存在下,以中等至高产率获得了各种3-亚磺酰基苯并呋喃或3-硒代苯并呋喃。
PdCl<sub>2</sub>-Promoted Electrophilic Annulation of 2-Alkynylphenol Derivatives with Disulfides or Diselenides in the Presence of Iodine
作者:Hui-Ai Du、Xing-Guo Zhang、Ri-Yuan Tang、Jin-Heng Li
DOI:10.1021/jo9016309
日期:2009.10.16
of 3-chalcogen-benzo[b]furans via palladium-promoted annulation reactions of 2-alkynylphenol derivatives with disulfides or diselenides and iodide has been developed. In the presence of I2 and PdCl2, both 3-sulfenylbenzofurans and 3-selenenylbenzofurans were selectively prepared from the cyclization of 2-alkynyanisoles with disulfides or diselenides in moderate to excellent yields.
通过2-炔基苯酚衍生物与二硫化物或二硒化物和碘化物的钯促进的环化反应,已开发出有效合成3-硫属元素-苯并[ b ]呋喃的方法。在I 2和PdCl 2的存在下,由2-炔基吲哚与二硫化物或二硒化物的环化反应选择性地制备了3-亚磺酰基苯并呋喃和3-硒烯苯并呋喃,且产率中等至优异。
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
A Green and Efficient Approach for the Synthesis of 3-Chalcogen Benzo[<i>b</i>]Furans <i>via</i> I<sub>2</sub>-Mediated Cascade Annulation Reaction of 2-Alkynylanisoles at Room Temperature in Water
Abstract An efficient and green aqueous protocol to access 3-chalcogen benzo[b]furan derivatives has been developed. The reaction can proceed via I2-mediated intramolecular annulationreaction of 2-alkynylanisoles with diaryl disulfides (diselenides) in water or undersolvent-freeconditions at room temperature. With the participation of I2, a variety of 3-chalcogen benzo[b]furan derivatives were obtained
A mild, practical, metal and oxidant-free methodology for the synthesis of various C-3 selenylated benzo[b]furan derivatives was developed through the intramolecular cyclization of alkynes promoted with diselenides via electrooxidation. A wide range of selenium-substituted benzo[b]furan derivatives were obtained in good to excellent yields with high regioselectivity under constant current in an undivided
通过用二硒化物通过电氧化促进炔烃的分子内环化,开发了一种温和、实用、无金属和无氧化剂的方法,用于合成各种 C-3 硒化苯并[ b ]呋喃衍生物。在分别配备碳和铂板作为阳极和阴极的未分隔电池中,在恒定电流下以良好至优异的产率获得了范围广泛的硒取代的苯并[ b ]呋喃衍生物,具有高区域选择性。此外,收敛方法表现出良好的官能团耐受性,并且可以很容易地以良好的效率进行放大,从而从简单、容易获得的起始材料中快速获得各种硒化苯并[ b ]呋喃衍生物。