1I must apologize
, this has been discussed before
Post 437037
(Organikum: "precipating of copper", Chemicals & Equipment).
Dunno how I didn't find it when I originally used TFSE.
2Added a steel dishwashing scrubbing pad to CuSO4 soln. It warmed up and copper was pptd almost immediately. Useful to know.
Thanks Ragnaroekk.
3Antoncho: "Noone wants that Cu powder in Br-vanillin hydrolysis, cause CuO (made in situ from CuSO4) will work none worse (actually, better). This comes from both Uemura's experience and that Japanese patent (in TFSE)."
* As I said before, I doubt if my failure was related to the catalyst, but I thought that next time maybe I should work strictly according to
Patent US3855306
so that if it still doesn't work it's easier to guess why.
* In
https://www.thevespiary.org/rhodium/Rhodium/chemistry/iodovanillin.html
, it says:
'Example 3 was also repeated using from 5 to 10 mole % of cuprous oxide, cuprous chloride, cuprous iodide and copper dust, as the catalyst for conversion of the iodovanillin to hydroxyvanillin. Recovery of 5-hydroxyvanillin was 80-85% (remainder vanillin) with copper dust, from 70-80% with the copper oxide or salts.'
This suggests that the Cu powder may be a little more effective ?
* For some reason I can't find the Jap patent you're referring to, but then we've already established that I need to improve my FSE skills (not to mention chemistry).
4Antoncho: "Gos`h!", "Hey, people, c'mon!", "And of course"
This is why you are moderator,
and I, a mere participator.