Described herein is the use of N=N double bond of azobenzene as both directing group
and radical acceptor in one-reaction protocol for the first time. An efficient pathway
for the Pd-catalyzed regiospecific ortho-acylation of azoarenes using benzylic ethers as acyl equivalents has been achieved.
In the absence of palladium catalyst, amide compounds were formed by the reaction
of azoarenes with benzylic ethers under certain conditions. Various mono-acylazobenzene
and amide compounds were obtained in good yields (35 examples). The mono-acylated
products and amide products could be easily controlled by palladium catalyst.
Key words
azobenzenes - synthetic methods - radical reaction - directing group - benzylic ether
- amide compounds