As for the messed up batch, where it was neutralized before the pinacol, and yielded a strange color change...

There was a upper red layer, and lower yellow layer.  It was thought the red layer was the oil/dcm, but turns out it was the yellow lower layer which was soluble in the dcm.  The aqueous yellow layer was back extracted along with the yellow oil layer. 

This will proceed to pinacol, and see what turns out... At this point it is probably all trash, but perhaps something will come out of it.

disclaimer: this is going to be an incredibly long post because i see you're having a couple problems and are definitely putting forth effort.  i hate to see large amounts of safrole go through so much labor only to go to waste.  it breaks my heart    so i'll do the best i can to shed some light.

ok i'll start at the beginning, the peracid oxidation and chronologically work my way down, covering as many helpful details as possible.  these details are perhaps overkill but i think it might help you get the jist of things.  when referring to the product of the peracid oxidation i'm going to refer to the glycol as your product, but the product of the peracid oxidation actually depends.  there are 3 possible products of the peracid oxidation and all 3 are usable/desirable, in other words all 3 of these products - when tossed into the pinacol rearrangement - will react to completion to yield mdp2p (i'm speaking generally, of course some of all 3 will react to form by-products in small amounts too but i'm not going to go there).  if you run the unbuffered peracid oxidation then the reaction is quite acidic and has more of a reputation to have the potential to create more by-products than the buffered reaction due to this reason.  in my personal opinion, and in retrospect, i would recommend that you just do the unbuffered peracid oxidation even though it's yields are traditionally a little lower than the buffered.  the reason for that is to not complicate things too much, just shoot for success for now even if the yields are lower than the buffered route.  once you have success a couple times or however many times it takes for you to feel comfortable with these reactions, then go ahead and run the buffered and focus on improving yields.  but for now let's focus on success, then focus on getting more comfortable with it.  once you know you have it down then focus on improving yields and efficiency.

the unbuffered peracid oxidation will yield the epoxide only as an intermediary compound, due to the solution being so acidic, the epoxide always reacts to form the glycol.  once the peracid (performic or peracetic) oxidizes your product, the peracid no longer has that extra oxygen so your peracid has now returned back to being the original acid (formic or acetic).  due to the presence of excess acid (formic or acetic), some of your glycol will become an ester.  if you used peracetic acid, meaning you will have acetic acid in the solution once it loses that extra oxygen, then the name of the ester is isosafrole acetyl glycol.  if you used performic acid which leads to formic acid within the solution, then the name of the ester is isosafrole monoformyl glycol.  so for the unbuffered reaction you get a mix of the glycol and the glycol ester, which is fine as both will yield mdp2p.

the buffered peracid oxidation can actually yield the epoxide as the end product.  this is because the buffered reaction doesn't have the excess acid that the unbuffered does.  if you goof up the calculations while scaling up/down your reactants and get the ratios of acid/base wrong then that will change the outcome.  but let's say you run the buffered reaction to perfection, you will not get the ester at all because there will not be enough excess acid for that to happen.  not only that but there will not be enough excess acid for all the epoxide to become the glycol, some of the epoxide will become the glycol but not all of it, the amount of excess acid will be the limiting reagent in that little equation.  so the buffered reaction will yield a combination of epoxide and glycol, the ratio of epoxide to glycol depends and isn't worth discussing because both work just fine to yield mdp2p.

for the peracid oxidation it sounds like you have it down now.  you pulled off the reaction and fractal filled you in on how it's supposed to be worked up which was with water washes, back-extract from the water washes per jon, pool all the dcm together and distill off the dcm, leaving the somewhat crude glycol which is fine for the next step.  don't distill the glycol, the only distillation for this reaction will be distilling off the dcm at atmospheric pressure.  i had completely forgotten that chromic instructs a 5% NaOH wash after the peracid oxidation, it's been some years since i've read his write-up.

it sounds like you're good with running the pinacol rearrangement with no problem, but you skipped basic water washes, understandably due to the problems it caused when you washed the glycol.  but the pinacol rearrangement is the reaction that requires the basic water wash to help neutralize residual acid.  water is fairly soluble in dcm, because of dcm's dielectric constant being higher than other non-polar solvents such as toluene/xylene.  i'm not saying to use toluene/xylene, definitely stick with the dcm.  i just wanted to let you know that since there will absolutely be water present in the dcm, and that since the water is very acidic, that means your dcm will be containing some of that acidic water.  since you didn't do a base wash your dcm had acidic water in it, some of it probably co-distilled with your dcm but i'd expect some to remain behind with your crude mdp2p.  then you went to vac distill the crude mdp2p with high heat and the presence of acid, so there goes your mdp2p :\  so what you want to do after you extract the crude mdp2p with dcm, you'll want to wash the dcm 3 times with a 5% NaHCO3 solution.  for the first 5% NaHCO3 wash just gently rock it back and forth, do a thorough wash but try to be gentle and patient, the reason for this is to avoid a potential emulsion since you'll be making a lot of base salts during then neutralization with this wash.  for the second and third 5% NaHCO3 washes go ahead and shake vigorously.  now you'll want to do one more wash before distilling anything.  wash it one last time really well with a saturated brine solution, do 2 brine washes if you want.  the purpose of these washes are to remove any residual small amount of NaHCO3 that is present in your dcm from the basic washes.  if you want, you can back-extract from those washes with fresh dcm but if you do back-extract then you'll want to take the dcm you used to back-extract from the washes and wash that dcm with a saturated brine once.  THEN pool that back-extracted dcm with the rest of your dcm from your 3 extractions earlier.  it sounds very redundant i know and it is very redundant.  but my rule is to be very anal about making sure there is no presence of excess acid or base with your crude mdp2p, it's good to be very anal about that so there is less risk of polymerization and side reactions happening, cleavage of the md bridge, etc, from high heat + mdp2p + acid or base.  the reason for the one saturated brine wash on the dcm you use to back-extract from the washes with, is because those washes when pooled together is a weak NaHCO3 solution full of impurities and base salts.  you want to rule out any of that NaHCO3 getting into the dcm you use to back-extract.  yeah NaHCO3 is a weak base and yeah there isn't much in those washes but it's better to just be anal about it b/c you've put in too much work to play russian roulette over a preventable mistake.  since you're just looking to find success your first time, my opinion is to not do the back-extraction for the pinacol rearrangement this time around.  just do the reaction, extract, do the washes, then distill off the dcm, then vacuum distill the crude mdp2p.  once you've had success and have the hang of all this, then you'll work towards upping your yields and then you'll worry about the back-extract.  just keep in mind about dcm and water being more soluble in one another than other non-polar solvents, so you're aware of dcm's ability to have water in it and since it has water in it, it can have whatever is dissolved in the water as well and carry some of that over to the dcm.  the other side to that is that some of the water you use for washes, etc, will have some of your precious dcm in it as well.  so if you use a total of 1000ml dcm to extract with, once you go through washes, etc, and distill off the dcm you may notice you only get 800ml dcm back.  that 800ml dcm is a completely made up number i used as an example only, that example isn't based on solubility vs volume calculations or anything, so the real amount may be nowhere near that number, it's just an example.  so if you're losing dcm due to some of it being in the water that is being discarded, then you'll know some of your mdp2p will be discarded with the water washes too.  but that's ok, just focus on success for now.  once you're successful then go back and try back-extracting, etc.

a note about the basic wash that's part of the work-up after the pinacol rearrangement: the NaHCO3 solution will do just fine for neutralizing the acidic reaction solution as long as you use enough of it, no need for NaOH.  you can use 5% NaOH here as chromic instructs but i'd err on the side of caution and just go with NaHCO3 because it's a weaker base.  why does that matter?  because if there's residual NaOH present in your crude ketone then you vacuum distill it, NaOH has a bad reputation for polymerizing mdp2p when heated together. 

VL is absolutely right.  regarding the washes it's best to trust your eyes over the instructions.  if it says 3 washes but your 3rd wash still removed color then keep going until the washes aren't removing any color.  what VL says about byproducts reducing your yields is dead-on.  if you do a sloppy work-up, half-ass the washes, then you're crude mdp2p will be much more crude and impure than it should be.  what that means is when you heat it up really hot to vac distill it, side reactions can occur and even worse, polymerization or tar formation can occur, once that happens - that shit is so thick it will trap the mdp2p from distilling over.

you shouldn't be getting any red colored distillate at any point.  the distilled dcm should come over clear, perhaps a little cloudy if there's water in it.  isosafrole should distill over clear, at worst with a yellowish tinge.  if it has a yellowish tinge (a more regular yellow color, not the fluorescent type of yellow associated with mdp2p) then that's most likely from some unreacted safrole which is present, that's ok if there's a very small amount of unreacted safrole present i wouldn't sweat it.  mdp2p's color when pure is disputed somewhat but the general consensus of 99.9% of us will probably agree that the mdp2p should distill over anywhere from a fluorescent yellow color - to a fluorescent yellow with a slight antifreeze green tinge depending on your lighting - to a yellowish/greenish color that might look more greenish than yellow.  if you're distilling over fractions that contain the red/purple by-products that VL mentioned then you're most likely distilling way too fast - applying way too much heat and you're driving the impurities over.  these impurities can co-distill with water to some extent, but you definitely should not see any distillate coming over that is anything resembling a reddish to purplish range of colors because all water will be removed under the vacuum atmosphere at a much lower temp then safrole/isosafrole/mdp2p, however if you go crazy with the heat then you might make the temp spike so high and fast that you just distill all those fractions over together as one big mess.  distillations suck i know.  distilling dcm is a piece of cake cuz it's so volatile but aside from that, the distillations take a long time and you have to do a lot of them but you need to be patient and be sure to not go crazy with the heat knob on your hotplate.  vac distillations are even more of a pain in the ass cuz they take even longer.  you just need to get good and accurate and being able to zero in on the desired temperature and knock those distillates over one fraction at a time.  after doing it enough times you'll probably get a good feel for what heat setting corresponds with a particular temperature scope for water baths and then a different scope for oil baths, unless you use your hotplate in a place where the ambient temp fluctuates of course.  in my opinion it's fine to overshoot the desired bp temp to drive over that last little bit of mdp2p during a vac distillation because i hate when there's that last little bit of fluorescent yellow in the distilling flask and doesn't want to come over, just don't go too crazy with it.  you want to keep track of the temp of your bath and also your distillation thermometer.  download truecrypt to make an encrypted volume and keep lab notes, store them in the encrypted volume with very strong encryption.  lab notes are incriminating but also very helpful when trying to troubleshoot especially if you're trying new reactions that you're not experienced with yet.

good luck

you said the temp shows a 20c difference in temp, but that's referring to the distillation thermometer right?  if so then that's the temp of the oil that is making contact with the distillation thermometer, it doesn't correlate with the temp of the bath.  in other words your bath may still be too hot.  that's why you should also use a thermometer in your baths as well so you aren't flying blind regarding the temp of your baths.  what did the thermometer in your oil bath say?  if you don't have one or didn't use one then going forward you definitely should, i use a digital candy/oil thermometer that clips right onto the bath but you can use a mercury thermometer too if you can find a way to secure it in place.  what was the fastest drip-rate of the distillate?  just trying to troubleshoot to see if you might've been applying too much heat and distilling it too fast cuz i've definitely never seen a colored impurity come over during vacuum distillation before but i always take vac distillations slow and steady but i've definitely driven over impurities a couple times in the past when i was somewhat new to distilling.  i used way too much heat and this caused the distillation to go too fast, i was able to tell that was the case because the drip-rate of the distillate was too fast and of course my bath thermometer showed that i had gotten a little hasty and overshot the desired temp by quite a bit.

if you had a thermometer in your bath and you know for sure that the temp wasn't that high then i'm not sure what the red impurity that's coming over as a distillate could be.  because that logic would mean that the red impurity is something that actually has a bp close to that of mdp2p and i've definitely never seen anything like that before.  take some of the distilled red oil and smell it, what does it smell like?  mdp2p smells entirely different from safrole/isosafrole.  as many others before me have said, it has a nice floral-type smell.

you can always take just a small sample of that red oil and do a bisulfite test on it, see if it forms the adduct.  sodium metabisulfite should be easy to find if you have home wine making stores around you, it's also quite cheap.  if the red oil does form the adduct you should be able to remove the red impurity from it by purifying the adduct itself.  if you've never prepared an adduct from a ketone or aldehyde before then you may want to do the procedure on acetone first as a test.  the acetone will form an adduct a LOT quicker than your red oil will, if your red oil even forms an adduct at all.  that is because the acetone is very pure whereas your red oil is impure.  the adduct formation happens just like crystallization of salts do in the sense that if your freebase is very impure then you'll run into crystallization problems, you might get butt-ugly crystals that take a long time to form or, more likely, your crystals will oil out.  if the red oil does form an adduct then definitely report back.  forming the bisulfite adduct is IMO the worst purification option available to you in regards to purifying impure mdp2p.  even if you're able to form a beautiful looking adduct from all your mdp2p, once you recover the mdp2p again you'll notice considerable losses and that's best case scenario from my experience.  personally i would only entertain the idea of forming the adduct as a way to test a small sample of the red oil, anything more than that is a waste but that's just my opinion based on past frustrations.

since we can't identify the red impurity there isn't any way to say how it'd react in the al/hg.  the al/hg is one hell of a reducing agent.  it can work wonders and even reduce fairly impure ketone.  but the more impure the ketone is the lower your yield will be, not just because there's less actual ketone present in that "impure ketone" but those impurities will cause headaches for sure.  impurities such as safrole/isosafrole aren't a problem but when your ketone is impure enough to where it has colored impurites that's a good sign that you're going to be lucky to get anything out of it.  having said that i've reduced very crappy impure ketone before.  a long time ago i couldn't afford a vac pump yet and was running the benzo wacker.  to try to get a somewhat decent ketone from that tarry mess of a reaction i used the most selective non-polar solvent that i had readily available to me which was heptane.  the tar wasn't soluble in heptane so the extractions were very clean, the extractions were fluorescent yellow.  but it turns out the ketone wasn't all that soluble in heptane either because it took 20 extractions before the heptane stopped picking up fluorescent yellow color.  the heptane was washed as normal then the heptane was distilled off.  during this distillation the ketone/heptane in the distilling flask began to turn red then it turned dark cranberry red by the time all the heptane had been distilled off.  i remember the dark red ketone smelled kind of floral and had a kind of medicinal scent to it.  i had seen that "medicinal scent smell" comment made many times on the hive but in my case it had a hint of an almost menthol vicks inhaler scent to it, the floral scent was the strongest and the medicinal vicks inhaler-ish scent was definitely noticeable but not as strong as the floral scent.  funny that there would be a vicks inhaler scent from something designated to be taken with vicks inhaler whiffs later on...     anyway, that "medicinal scent" is an impurity of some kind because once i finally got a vac pump and got better at vac distillations so that i was getting some very beautiful from then on out, the smell of the more pure ketone did not have the "medicinal scent" it only had the floral scent.  so i took that red oil and reduced it anyway.  i think it was maybe 5-ish grams of red oil or something like that, maybe a few grams more.  did the al/hg, worked it up and ended up with a clear oil instead of a salt.  i put the oil in a pyrex pan and had a fan blow on it hoping to dry out the oil.  it eventually did but it took forever, like a week or longer.  i scraped up the dried oil which was just a whitish solid that looked nothing like it should look like.  not only that but the yield was under a gram, it was somewhere around 500mg give or take.  it was such a low yield that i didn't bother to pursue it any further, if there was a decent enough yield i would've recrystallized from anhydrous ipa, flood with acetone, freeze precipitate.  then take that recrystallized product and do a marquis test on it then do a melting point test on it.  then if i'm really ballsy take a tiny test like 1mg, 10mg, 20mg, 40mg, 80mg.  but bio-assaying something that is unidentifiable is really stupid and i don't know if i would've had the balls to take a random compound made from something speculated to be ketone with an unknown impurity.  tossing unknown compounds into reactions just produce unknown results.  also the red ketone i had was from a different reaction entirely, so my impurities would've been different from yours.  the only way it'd be the same is if the impurity was a degradation product of mdp2p and our mdp2p degraded through the same mechanism.  there's just too many unknowns with going any further with the red ketone.

since the adduct is a crap way to purify and reducing the red oil would mean you would want to consume the result which i wouldn't recommend doing.  my personal opinion would be to take the red oil and any crude undistilled ketone you have left (if it hasn't polymerized, etc) and toss it in dcm.  i would work them up separately just in case the undistilled ketone is in bad shape due to exposure to heat while in the presence of impurities, that way if the undistilled ketone causes problems through this little work-up then it won't effect the distilled red oil too.  anyway i'd toss them both back in some dcm, then do the washes i described above, then distill off the dcm, then vac distill the suspected crude ketone.  basically re-doing everything but this time including the basic washes (and of course the brine washes after that to remove any residual basic solution).  i would vac distill the 2 crude ketones separately also for the same reason stated above, just in case that undistilled ketone causes problems.  going through another work-up like this again will definitely hit you hard with mechanical losses but i can't think of any better-case scenario.  if anyone has a better idea definitely chime in cuz this is the best solution i can come up with.

For gassing:
H2So4 with Nacl

OR

HCL with CaCl

?

Both will be run with a CaCl dryer tube afterwards regardless...

Or is there a better method?
I hear the Nacl and sulfuric will produce dry gas...but would run a dryer after it to be extra safe...

How do you calculate how much is required to gas "Y" amount?

Hi Sedit.

Another valuable member.  Appreciate it. 

Great suggestion reading on the moles will be useful. 

With the H2SO4 and NaCl, is a CaCl dryer a nice addition to ensure? 

Just a side note, for those who can relate.  Isnt breaking glass such a nice occasion hah.  Getting a nice deep cut on the finger using a claisen for something it wasnt originally designed for a.k.a. fitting it to a carboy and than finishing off with banging a funnel to hard and knocking half the ground joint off.  YES.  A towel is a necessary accessory for glass sleeptime.

Well what color is iodosafrole? :rhetorical: Clean your product up better. Way off topic here though, nothing to do with the reaction the thread is about lol There will always be side reactions no matter the reaction used, these byproducts even in very small amounts can change the color completely.

Yeah it was a kinda dumb question that I kinda knew, so aside from the fact I was drunk, and it was late, I dont really know why I pposted it, sorry

I  was going to remove it, but now...I guess it stays. My head feeels likke a junkshop, and I KNOW i dont like gettin pissed!!  Talk about "silly season"

and yes, could be cleaner, 

a very stale fresh

No buffered is the way to go if you're looking to yield more at least. It's more efficient to gas longer as you have to filter less times. Just make sure you rinse crystals with a bit more fresh anhydrous toluene to collect traces of freebase left behind in between filtrations, none to waste. Toluene will evaporate cleanly, just have to give it time. You should still do a wash or recrystallization or both though. No the heat will not damage it, temp can not go above the BP of the solvent used unless super heating occurs, if it was not bumping than this is not occurring. Sounds like things worked out good, congrats.

Hi Lugh and Fractal.

Nice to hear that success may have been reached.

On the forum access is denied it appears.  Is post count required?

Happy Christmas Eve and Happy Hannukah.

On the forum access is denied it appears.  Is post count required?

There's a dedicated thread for newbees to post in:

https://the-collective.ws/forum/index.php?topic=21976.0

so access the entire forum can be achieved