Nitromethane, a volatile and toxic organic compound, is commonly used as solvent for organic and catalytic reactions. In order to find an alternative for this specific nitro-containing organic solvent, the performance of some nitro-functionalizedimidazoliumsalts such as 1-methyl-3-(4-nitrobenzyl)imidazolium hexafluorophosphate, 1-methyl-3-(4-nitrobenzyl)imidazolium tetrafluoroborate, 1-methyl-3-
Cobalt‐Catalyzed Temperature‐Dependent Annulation of 3‐Aryl‐1,2,4‐oxadiazolones with 1,3‐Diynes: An Approach to π‐Conjugated Molecules
作者:Wenge Zhang、Hongji Li、Lei Wang
DOI:10.1002/adsc.201801165
日期:2019.6.18
A Cobalt‐catalyzedannulation of 3‐aryl‐1,2,4‐oxadiazolones with 1,3‐diynes has been developed, in which reaction temperature variation considerably affects the cyclization orientation and afforded structurely distinctive products in good yields and high regioselectivity. Additionally, the late‐stage transformation of the cyclization products into N‐containing heterocycles is also demonstrated.
The Co(II)-catalyzed selective C–H alkenylation of picolinamides with 1,3-diynes has been developed. This protocol can be applied to a variety of 1,3-diynes. In addition, both symmetrical and unsymmetrical internal alkynes were well tolerated, affording the corresponding alkenyl arenes. Moreover, control experiments indicated that C–H bond cleavage may be involved in the rate-determining step. Furthermore
We developed a technique mediated by visible light for the aerobic homocoupling of terminal alkynes to synthesize 1,3-conjugated diynes using a copper(I) chloride catalyst at room temperature. Compared with previously reported thermal processes, this photochemical method is simple, uses only mild reaction conditions, produces high yields and works well for substrates with electron-withdrawing groups
polyacrylonitrile fiber, capable of acting as a novel support for polymer-supported copper catalyst in terminal alkyne homocoupling reactions, is presented. Detailed characterization by inductively coupled plasma (ICP) analysis, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) confirmed the changes and stability of the fiber catalyst during the modification and utilization