Post 208821 (missing)
(LaBTop: "The ONE and ONLY buffered Performic", Methods Discourse)Here's first the conversion from Safrole to Isosafrole done by LaBTop, Osmiums simple route was followed, yields are ~95% without vacuum, ~99% with vacuum :
No vacuum:
Weight 130 kg distilled safrole and add 2% = 2.6 kg KOH grinded flakes or pellets >98%.
KOH flakes are in some countries 85%, the 15% rest is water, check it on the label.
Then heat up. At 100 C the eventual 15% water will start evaporating, or, when 98% KOH was used, only a small amount of water will come off.
This removal of water is critical to the reaction, water present when refluxing will totally stop all isomerization.
Add more heat until all water is evaporated. Then at last connect a reflux condenser vertical on your vessel and continue heating until the safrole starts boiling, without vacuum, reflux will be constant at circa 232 C until boiling stops, that means it has nearly all converted to higher boiling Iso.
Do NOT crank up the heat then, but disconnect heating and let cool to roomtemperature. Reaction takes roughly 3 hours for non vacuum. You now have ~95% Isosafrole which you use for the MDP2P conversion step. You could vacuumdistillate it now, to get >99% Isosafrole, but that seems to be no option for the ones who choose for this approach, they probably have no vacuum source, and ~5% safrole will not really interfere with the MDP2P step, so do it under atmospheric pressure.
LaBTop says to use 98% KOH,according to Sigma-Aldrich,there is no such thing as 98% KOH,at least they don't carry such thing,their purest is 90%,raf has probably 85% as other bees.At 100C,nothing will start to evapourate,at 150 some water evapourates,at 200C we could assume most is out and start the actual reflux.Raf doesn't know how he is going to measure the rx temp,but he'll figure out something,hopefully.LaBTop mentions nothing about stirring but raf thinks some is necessary,we'll see :) .This time he uses 250 grams of safrole rather than 500 gr.Loss of 500 gr is worse than loss of 250 gr.
Post 306186 (https://www.thevespiary.org/talk/index.php?topic=8828.msg30618600#msg30618600)
(abacus: "Easy iso", Methods Discourse). Swim only had aspirator and basic Hotplate/stirrer and got isosafrole in ~ 90% yield (B.P. test). This isosafrole was then utilised in Labtops buffered performic to achieve a 68% w/w yield of P2P/isosafrole on first ever attempt using poor equipment and questionable technique. Using the technique in abacus's writeup is the simplest there is and it works. No need for CAO or additional filtering. It doesn't get any easier. ;)