ISSUE:

Consulting in different resources of Organic Chemistry, I have found two reactions for the objective indicated in the matter:

First reaction:


Second reaction:


But, I can't find the reaction mechanism by which they occur. Which would be necessary for an exercise, the conversion of m-dinitrobenzene to m-chloronitrobenzene, in which I want to introduce one of these two reactions as an intermediate step.

Thank you very much in advance.

Hello fellow member,
if you can't find the mechanisms it is because perhaps they are not exactly known, think that it is a selective reduction, and in which free radicals may be involved. In any Organic Chemistry book they will tell you the reaction and what is obtained, but if you want to go deeper I think you have to get into scientific research pages.