A direct electrochemical phosphine-mediated deoxygenative [3 + 2] cycloaddition strategy for oxazole synthesis is described, employing naturally abundant and inexpensive carboxylic acids as starting materials. This method is performed in a green and sustainable catalytic system, and avoids the use of transition metals and toxic oxidants. Good functional group tolerance, the success of gram-scale experiments
Electrochemically promoted N-heterocyclic carbene polymer-catalyzed cycloaddition of aldehyde with isocyanide acetate
作者:Chu-Hong Ou、Ying-Ming Pan、Hai-Tao Tang
DOI:10.1007/s11426-022-1360-3
日期:2022.10
a porous organic polymer with NHC as the core structure to solve the above problems. The catalytic performance of the polymer was tested in this work. The polymer can successfully catalyze the cycloaddition reaction of aldehyde and ethyl isocyanoacetate under electro-oxidation. The results showed that the polymer catalyst can be recycled and had higher catalytic activity than homogeneous NHC. The developed
Copper(<scp>i</scp>)-catalyzed tandem synthesis of 4,5-functionalized oxazoles from isocyanoacetate and aldehydes
作者:Yuting Wan、Jieqing Wu、Hongfei Ma、Hongjun Zhu、Patrick J. Walsh、Yufeng Li
DOI:10.1039/d2nj03162k
日期:——
Oxazoles are among the most important heterocyclic scaffolds in the fields of natural products and medicinal chemistry. Herein is developed a tandem reaction for the synthesis of a diverse array of 4,5-difunctionalized oxazoles utilizing easily-accessible ethyl 2-isocyanoacetate and aldehydes (26 examples, 31–83% yields). This cascade reaction is facilitated by catalytic CuBr and molecular oxygen as