Hi All!.
   I´m planning this week on scaling-up the benzoquinone wacker,because it´s the most tedious part for me,mostly because the palladium pre-stirring,7 hours reaction wait without doing anything,the extraction and washes after the reaction,long distilling time,....So i want to make only once ,mostly too about that and because too it´s a very dirty process in my experience,finishing with room totally plenty of thrash all over,fumes from the oil bath when distilling at high temp,....
    So,i think  remember and old Hive post talking about the wacker suffers from scaling-up about yields,taking like reference Bright Star´s/Methylaman´s amounts.But can´t remember at what level about scalling-up.
   I´m thinking on run a 3X-4x scale of the amounts,with DMF not methanol,so....Any problem taking all quantites and making a 3x -4x adaptation,or maybe need to adjust something to get equal yields,....posibly can reduce a llittle palladium amount?,.....it´s worth it the addition of  CuCl2 to help palladium?,.....,,
    I was reading too that famous articles  about "powered wacker" or named similar,don´t remeber,and  seems the amounts can vary a little and can make enough diferrence  on yields to be worth it.
   Any advice about that can be great,or if you have any amounts that worked well about scale-up that reaction will be great too.Thank´s!

^ Shake is 110% correct on everything except about the DMA SRV O2 wacker, i can't comment one way or another about that.

you were going to scale it up 3-4x larger than MethylMan's scale which was 178g safrole?  yes you can scale it up that high just be aware that the reaction becomes more exothermic the larger you scale it.  it will reflux on its own without external heat at large scale reactions.  i don't have experience with large scale reactions like that, i'm just repeating what i've been told.  i've actually noticed it become slightly more exothermic going from microscale (no exothermia at all) to moderate scale (a little bit of exothermia but not much) so i can see how the much larger scale reactions will be even more exothermic to the point where it will reflux on its own.

i can speak from experience that i prefer toluene over DCM as an extraction solvent, but Shake is right you need more toluene than DCM because it's less selective than DCM is and you want to make sure you get all the ketone you can right?  i extract only 3 times but i use more solvent than MethylMan uses b/c i used tolly and he used DCM.  why is toluene better than DCM in my opinion?  because the toluene is less soluble in water.  as you extract and do the washes, you lose some solvent (and that means you also lose some ketone) to the water layer.  DCM is more soluble in water than toluene.  so after the extractions and washes, you lose less overall volume percentage of toluene than DCM.  so, because of that, my overall yield of ketone has been higher.

i've used heptane and naptha to extract from the benzo wacker in the past also and those solvents are way too selective, much more selective than toluene.  in fact i had to do 20+ extractions with heptane and naptha to get all the ketone and even then my yields were very very low because it couldn't dissolve the tar.  so there was TONS of mechanical losses b/c the solvent was too selective to dissolve the tar and, thus, extract the ketone that is trapped on those tarballs and believe you me, there's a considerably amount of ketone in those tar balls.  i took one of the tar balls and squeezed it (with gloves on of course) and could see some ketone ooze out.

the problem with the benzo wacker is that it's messy messy messy.  as shake said, the more benzo you use, the more mess there is.  i wouldn't use less PdCl2 than MethylMan states but you can definitely use less benzoquinone.  here are my personal notes on the amount of benzoquinone:

The standard write-up by MethylMan uses a 1.265 molar equivalent of p-Benzoquinone to Safrole.  Since p-Benzoquinone donates 2 oxygen atoms and Safrole only needs one of them, that means there only needs to be half the molar amount of p-Benzoquinone to Safrole.  Keep in mind you always want the p-Benzoquinone to be the limiting reagent and not your all-important Safrole, you want to make sure all the Safrole reacts.  Dropping the amount of p-Benzoquinone will result in a less messy, less tarry work-up so you’ll lose less of your goods to mechanical losses.  If you have good quality pure p-Benzoquinone that is canary yellow and highly irritating to be around then you might want to scale down to a 0.75 molar equivalent of p-Benzoquinone to Safrole, that still gives you a 0.25 molar excess but cuts down on the amount used drastically for a less messy work-up.  If you’re p-Benzoquinone is less pure but still over 90+ pure, mustard dirty yellow or yellowish brownish and highly irritating to be around then you may want to use an equal molar equivalent just to be sure there’s enough actual p-Benzoquinone, this would give you a 0.5 molar excess of p-Benzoquinone depending on the purity of it.  If you are truly uncertain about the purity of the p-Benzoquinone, if it’s brown/green/metallic gold/any color other than some shade of actual yellow then you may want to stick with MethylMan’s 1.265 molar excess of p-Benzoquinone.

Well,about CuCl2,have read works for recicling  palladium , isn´t it,during reaction time?.Maybe i´ve understud wrong it use,but anyway,...i´ve only asked because if someone have seen any improvement using it,but of course i´m not planning using it on this run .Only about curiosity!.
   On another hand,yes guys,we have talked on another thread time ago about using toluene to extract the ketone instead of DCM.Yes,since i proved it the first time,i have know it´s the better solvent to extract the ketone,without nasty emulsions DCM makes in my experiements when i working with basic solutions.
   So maybe we have to study hard the benzo wacker and try to make it a little more straight,try to get most posible crap out of the solution before distill our ketone,try to make extraction and washes more easy,...because...like you said guys....i finish always with a flask with aprox 25-20 % ketone expected trapped on the black tar,and can see ever the green ketone there looking at me saying:are you stupid enough to let me here...oh man...try to distill me again!only few ml more:D.
   One thing i was dreaming about ever it´s how many ketone it´s on the solvent when we hit the solution with acid water and the black oil falls from solution to the bottom of the flask...i always look at it,and seems it´s mostly the ketone amount expected.I have dreamed always on let the solution decant like 2 hours,to get most oil posible to the botttom,collect it,and go straight to washes,because that extractions of the solution eare really a painfull wth so big amount of water solution.
   Yes guys,i know ketone it´s a little soluble on that acid water,so we need to extract it from the solution with the toluene,...but how much ketone can be on that solution?Posible only with  1 toluene extraction after the separation it´s enough to catch most ketone.....understand me ...i´m talking only about less work that can result on aceptable yields for a wacker,like 70% it´s good enough.
    I have scuriosity about why Methylmans after flood reaction with acid water,don´t collect that oil and then make the extractions,when i´ve seen decantation it´s quickly enough too not to have to wait more like 10 minutes,....resulting on more extractions to get all the ketone?? ....when on other hand,for example Bright Star´s wacker,tolds about collect first the oil layer and the extract....Only what i know,it´s that once i make that,collected first the oi,the extracted several times,then miked both oil and extractions,and when gone to washes....freaking freaking emulsions,.....bad luck or maybe any reason to explain that??....I remember i was on the DCM/TOLUENE chamging time,so i can´t remeber what i´ve used,who knows...
  
   I usually put the reaction flask after reaction on freezer over night,and filter it next morning by gravity,i make the water washes,naoh washes,...and ever think i´m losting good amount ketone on that,but of course naoh washes are  totally necesary if we appreciate our distilling equipment.
   I use to begin distillation fractional,and when i´m sure only ketone it´s coming over,power off heat,change to little flask and continue with normal distillation without columm,because fractionally i have scorthed the ketone many time trying to get it out,and it´s a painfull.
   One time,i redistilled the ketone fractionally,and results on a pretty easy distillation like sass oil,without almost any scortched ketone on flask,so minimal loss.Maybe try that this time with all ketone recovered.
  So,like you can see,i follow common procedure,but still,and you know,extractions,washes and distillation can go really straight or can go like a nighmare.Almost good luck matter!.
 Then,maybe better will be run 2-3 wackers,collect the toluene from each,and distill all together,and supossed not much ketone looses.But who knows?
  I have think too on the peracetic process and anothers,but at this moment,i´m lazy enough to not experiment with new things and continue with methods i know work for me,and have necesary chemicals to run it.
  Have to say too,seems Palladium it´s getting more difficult and expensive to get to me,don´t know to others,so maybe on the future will be good thinking on the peracetic route or another that no use it.But like said,lazy man....

    

hexane will be on par with naptha and heptane as far as how efficient it is at being used as an extraction solvent in this reaction.  i would not recommend it, it's too selective.  you'll lose lots of ketone because those 3 solvents can't dissolve the tar enough to liberate the ketone so the ketone will stay trapped.  you'll get BEAUTIFUL yellow extractions in your solvent but you'll have to do like 15-20 extractions and you'll still get low yields it's just too selective.

CuCl2 is only needed for the O2 wacker where elemental oxygen is used as the oxygen donor.  with the benzoquinone wacker, the benzo is the oxygen donor, no need for CuCl2 there.  Lugh attached some nice pdf's, the wacker pdf he attached is regarding the atmospheric O2/dmf/pdcl2 wacker.  i would have to recommend against the O2 wacker, if you have benzo just do a benzo wacker.  otherwise just do peracid.  i definitely wouldn't waste my time on an O2 wacker, they're way too finicky

so in review: if you're doing a benzo wacker, forget the CuCl2.  if you want the benzo wacker to run cleaner then use pure, beautiful yellow benzo.  using more pure benzo means you can use less of it, if you have beautiful yellow benzoquinone as your source then use 0.75 molar equivalent benzo to safrole.  for every 1 mole of safrole use 0.75 moles of benzo.  if your benzo is dirty yellow, like mustard yellow then use equal molar benzo to safrole, for every 1 mole of safrole use 1 mole of benzo.  you'll see it runs MUCH MUCH cleaner (less tar) compared to MethylMan's 1.2 molar excess of benzo.

personally, after adding the HCl, i never decanted i just extracted really well 3 times with toluene.  yeah the dark oil will be on the bottom and the toluene will be on the top, but the toluene will dissolve a lot of the organic crap and its density is still lighter than that of the MeOH/HCl (aqueous) layer.  so the toluene will still be on top, just give it a couple minutes in the sep funnel to make sure the layers are separated.

yes toluene does get emulsions, but DCM does as well.  when doing the NaOH washes, do NOT shake them.  just rock it gently back and forth.  shaking will result in emulsions.  same goes with the brine washes just rock it gently or swirl it, do not shake it.  if you shake you'll get an emulsion.  the work-up is just so filthy that you can potentially get emulsions with toluene or DCM just as easily IMHO.  to not get emulsions during the work-up is all about technique.  you want agitation during the washes but not too much agitation.

most of the organic crap is soluble in the toluene except for perhaps some of the bigger tar chunks.  there are ways to limit the amount of tar so it will be a cleaner reaction but some of the methods are just a pain in the ass and it's easier to just deal with the tar that's present.  the best way to cut down on tar without adding more "pain in the ass" steps like freezing/filtering/etc, is to be sure to use very pure benzo like i said above, and use a much smaller molar amount.  it really makes a big difference.

i dont decant, i just add the hcl and let it stir for awhile.  then add toluene and agitate (stir or shake), pour everything into the sep funnel and give it time to separate.  it will separate into 2 layers, the top layer is toluene/organic crap and the bottom layer is the aqueous layer.  tap off the bottom aqueous layer back into the flask and add more toluene, etc, etc, (continue with the extractions)

CuCl₂ is added to recycle the Palladium do I don't really see how the oxidant has any effect on if this is needed or not. Its an electron transfer mechanism not a reactant so to speak.
 
Without it the "catalyst" are not really catalyst at all they are reactants...

Not my area of experties but I say use it unless ya'll can convince me otherwise.

Hey in my own defense, the ONLY two reasons I wrote up the damn things in the first place were that

1) I needed something that I could follow in my own writing that didn't skip over important details

2) so many guys on the Hive who were trying to pass along information were borderline illiterate when trying to write on forums. And I'm not talking about people for whom English was not their native language---I'm talking about people who were too scattered or lazy to even put spaces after periods (if they used periods at all). Things are much better today... I don't know why on that site so many people struggled with punctuation, grammar, focus, etc. Maybe it was all the  meth, I don't know.

I never claimed to be a scientist or tried to write that way.  I always thought it was obvious I wasn't one, despite that I tried to write it in a style that would be friendly to any chemists should they read it, yet also be possible for a layman to follow.

Also, what I wrote at the time was based 99% on work that had come before by other people. I just paid attention to visual details and included my observations about them. What I specialized in was writing things step-wise so they made fucking sense, to me and others as well. I never imagined people would be referring to them 10 years later.

methyl man, you have provided gold for us, really.. the community, the game, you alone have made us big steps in the war.. i am thankful greatly, i read the amalgum nitro write ups myself, i wrote write ups based on yours...you did very well.

they are beautiful.

it is the trust that people have in them, maybe they are too well written, because there was and has always been room for improvement.. methyl, i will say me and you are probly par for chem knowledge so dont worry i cant rip on you because you are more exp than me anyway..

i guess i want people to just pull away from the awesome write ups, test the boundarys,.. make progress you know??

Sorry to methyl bash 

Shake, sorry to sound so defensive there, I just re-read my post and realized how much so I sounded. I guess the word "hate" always triggers a little something in me. But also I think there's something else going on---I have been off cannabis for about 29 days now, and I think the last of it is leaving my system. Cue the spontaneous irritability! 29 days may not sound like a lot, but when you've been using it solidly 29 years, it is.

Anyway back to the main thrust, and I agree with you 100% of course, none of us should lean on old archaic methods, no matter how easy to follow. And it's very kind of you to say that my chem knowledge is on par with yours, but it is absolutely not, I assure you. I've read your stuff for a while and you are WAY ahead of me. Remember I took a break for 10 years here! Plus, I never really studied formally. So please, let's be real about that. I am much more likely to learn from you. I'm trying to catch up and am struggling. But it's fun to try...

I'm reminded of Sasha's quote:  "Orbitals are for mathematicians... organic chemistry is for those who like to cook!"

TV was around in the early-mid 1950s.

I'm not sure whether advancements in chemistry have kept pace with advancements in communications and information technology, though.

Okay, the benzo wacker is archaic. So what then is the latest, hottest breakthrough in olefin oxidation reactions? Believe me, I'd love to learn that there's something great that I didn't know about. I just haven't heard of it. Like everyone else, I'd like something clean and easy, cutting-edge, that uses easy to get non-watched reagents, with a breeze of a workup. Whatcha got?  

And it's true, I didn't pull the benzoquinone out of my ass---I pulled it out of Strike's ass!