If you care for lower d9 numbers from those parameters mix faster, run longer, run on the hotter side of those ballparks.
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Ptsa in toluene, Low temp for extended periods of time, anhydrous, yields high D9
Ptsa in DCM, low temp, for extended periods of time, anhydrous or not, yields high D8
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Is there an empirical way to determine dryness of glassware or otherwise?
sure; how long has the glass been out of the oven or desiccator
i dont know of any tricks here; the glass can have no visual moisture or āwetnessā and it can still have atmospheric moisture; really depends on the relative humidity of your environment and if you give it the ideal conditions to condense
clean w/ acetone then dry in vacuum oven @250C Full vacuum for @ least 4 hours. Allow to cool under full vac then you ready to go. I usually leave it overnight or 12 hours.
I was thinking of adding a vacuum port to a microwave and seeing what happenedā¦
i leave most of my gear either in the oven, under vacuum and at temp, or in a drybox such as;
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Using a proper schlenk system- Wash your glassware with anhydrous solvent and test itās water content before, and after your drying sop.
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Hereās something for someone to try:
1% Amberlyst - 15
1% IndiumTriFluoroMethaneSulfonate
3 parts heptane
1 part cbd isolate
Room temp - 50C (you choose)
I ran this recently goofing around and saw insanely clean and fast conversion
No real need to dry anything. inotf3 is a water friendly Lewis as far as I am concerned. Also amberlyst 15 seems to not care about water.
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How are you doing this?
damn genius
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and so does your wannabe expert talk. youāre way out of your league trying to teach or lecture anyone here.
funny how you come back with an even bigger mouth everytime your bullshit gets picked apart 
dude it was a joke, i donāt give a shit what you or anyone here thinks. i took that thread like i should have, as a sign that sharing anything of significance here is an invitation for undereducated shiznits to get angry about others actually putting their knowledge to good use. the really good stuff doesnāt get exchanged publicly here, and for exactly this reason.
if you wanna dick measure then explain how you think a liquids boiling point is a relevant measure in this case instead of its specific heat capacity (which is 50% higher for hexane vs. toluene).
yeah, i thought soā¦
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With @iLLnyeTheShatterGuy SOP ya listed, Iāve been wonderingā¦
Iāve been dissolving/mixing in my pTSA with my solvent of choice in about 100ml and adding all in 1 shot. No slow pours. All done at room temp. Exothermic spike was almost immediate. Also allowed me to add it prior to my feedstock in the reactor so I could release all at once if I wanna run inert without disturbing anything. Did one run like this and had less loss and ending in a cleaner (appearing) raw product. Plan to replicate again.
Theory behind thisā¦
Adding bits (albeit, safer) at a time allows for longer contact and residency time. By the time you add it all, thereās been an extra 15 minutes tacked in to the full RXN time therefore pushing the RXN past the time needed.
Also.
The acid needs time to melt down and homogenize with the solution (once again, taking more time). By pre dissolving in your solvent, it should be instantaneous (by my marked perception of almost immediate exothermic spike).
Take it for what itās worth.
Be cautious when doing this! This could cause a very volatile situation
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I add acid and homogenize under argon and then start my temp ramp till I see a light sweat on the condenser and run for 2 hours and then let cool down to 25c and start washes
Running inert will eliminate the CBN I found
This is with hexane - donāt go past 62/63c and have chiller ready to kick on if you do
2% PTSA in helptane at room temp had promising results .
Only ran once and only for 30 mins but that would be the next one I played around with if I had extra time
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do you know what āspecific heatā means?
did you go look up toluene vs hexane?
turns out it takes more joules to raise a kg of hexane by 1oC than a kg of tolueneā¦but given toluenes higher density, it take more joules to heat a LITER of toluene than a liter hexaneā¦thereās not a whole lot in itā¦
see: Liquids and Fluids - Specific Heats at engineetingtoolbox.
hexane: 2.26 kJ/kg.K density: 655g/liter => 1.48kJ/liter.K
toluene: 1.72 kJ/kg.K density: 867g/liter => 1.49kJ/liter.K
just a reminder that how you measure your 1:1 matters (1kg:1kg vs 1l:1kg makes a difference).
edit: and @roiplek is on point that going through the phase change is really where the heat sink isā¦
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This I donāt know much, in heptane or other hydrocarbonā¦ 
Using water, dealing with regular bentonites, one could expect some calcite (CaCo3), or gypsum (CaSO4.2H2O) to be leached out. Dealing with acidified one, some acid (I guess H2SO4) could be there.
Thus I assume there is not much to be dissolved in organic solvent.
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FTIR spectroscopy
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It is not consumed. But it does have an influence on the kinetic, to some extent.
In addition, the solvent can lso help to dissipate the heat.
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This is why drying your water washed solution, before column filtration is super important.
Also, the more acid, the quicker the reaction, also the hotter the exotherm, the more solvent, the more buffer one has for the exotherm to be absorbed.
There is a balancing act there fursure; between time:catalytic load:solvent dilution.
too little of solvent the exotherm wont be absorbed and itll overboil violently.
Too much solvent and the chances of a kinetic interaction is slightly reduced, just because the solute is more more widespread throughout the solution.
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Thatās the reason I recomend high stirring speeds with the right rotor
It compensates a lot of high solvent volume rxn s
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