B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>-Catalyzed cyclization of alkynes: direct synthesis of 3-silyl heterocyclic compounds
作者:Mengxing Li、Ting Wang、Zhenyu An、Rulong Yan
DOI:10.1039/d0cc04314a
日期:——
An efficient one-pot strategy for easy access to 3-silyl heterocyclic compounds was developed via a B(C6F5)3-catalyzed cycloaddition reaction of o-(1-alkynyl)(thio)anisoles or o-(1-alkynyl)-N-methylaniline.
Conversion of alkynes into 1,2-diketones using HFIP as sacrificial hydrogen donor and DMSO as dihydroxylating agent
作者:Raghuram Gujjarappa、Nagaraju Vodnala、V.P.R.K. Putta、Velma Ganga Reddy、Chandi C. Malakar
DOI:10.1016/j.tetlet.2019.151588
日期:2020.3
A metal-free and hypervalentiodine free conversion of internal alkynes into 1,2-diketo compounds has been described. The efficacy of the present protocol rely on the use of HFIP (1,1,1,3,3,3-Hexafluoro-2-propanol) as reducing agent of alkynes and DMSO as dihydroxylating agent of olefins to acquire the desired chemical transformations. The obtained 1,2-diketones were further transformed into useful
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
<scp>3‐Methylthio</scp>
‐benzo[
<i>b</i>
]furans/Thiophenes
<i>via</i>
Intramolecular Cyclization of
<scp>2‐Alkynylanisoles</scp>
/Sulfides Mediated by
<scp>DMSO</scp>
/
<scp>DMSO</scp>
‐
<i>d</i>
<sub>6</sub>
and
<scp>
SOCl
<sub>2</sub>
</scp>
作者:Beibei Zhang、Xiaoxian Li、Xuemin Li、Fengxia Sun、Yunfei Du
DOI:10.1002/cjoc.202000566
日期:2021.4
with SOCl2 and DMSO was conducted to conveniently furnish the biologically interesting 3‐(methylthio)‐benzo[b]furans/thiophenes via intramolecularcyclization. DMSO acts as a solvent as well as a sulfur source and can also be replaced with DMSO‐d6, enabling the incorporation of the SCD3 moiety of DMSO‐d6 to the 3‐position of the heterocyclic frameworks.
进行2-炔基苯甲醚/硫化物与SOCl 2和DMSO的反应以通过分子内环化方便地提供生物学上令人感兴趣的3-(甲硫基)-苯并[ b ]呋喃/噻吩。DMSO充当溶剂,以及作为硫源,也可以用替换DMSO- d 6,使SCD的掺入3 DMSO-的部分d 6到杂环框架的3位上。