By using the search engine for about ten minutes, the answer to your question was found. The terms used were isosafrole and isomer, this combination must have eluded you. It's in Methods Discourse, started 5-7-01 by wacko reaco in Post 189761 (https://www.thevespiary.org/talk/index.php?topic=9066.msg18976100#msg18976100)
(wacko_reaco: "isomerisation success (x2)", Methods Discourse), called "isomerization success (x2)" :) :) :)