moving from the oxime talk back over to the real topic at hand - antibody's al/hg oxime reduction.... i've run this reaction a number of times and it works flawlessly except for a couple failures i had which were exactly what Oerlikon reported on the previous 2 pages. i amalgamated in either EtOH or MeOH, i've tried it both ways and it seems as though when you run it with EtOH you're more likely to have to add ice cubes to the water bath to cool it down because it runs hotter and seems to gel up easier too. with MeOH it refluxes a little heavier but runs less of a chance of needing external cooling and doesn't gel up quite as easily as EtOH does. the downside to MeOH is that it's emulsion-prone during the toluene extractions after the reaction is done, however if you follow my advice below and use 35% NaOH solution (i think RoidRage posted these results first a couple pages back), then use of the 35% NaOH solution will prevent the bad emulsions you may get otherwise like if you used a more dilute 10% NaOH solution and whatnot. the stronger concentration NaOH solution gives the alcoholic/aqueous solution much more density than a more dilute NaOH solution. if you use MeOH then be sure to use pure MeOH, not the "denatured alcohol" crap from your local hardware. the denatured alcohol is a waste, you'll waste oxime and get crap yields. madprossor stated this many years ago on the hive, it really fucked up his yields bad and RoidRage stated the same thing a couple pages back i think. so be sure to use a pure alcohol for whichever you choose, for EtOH use 96% grain alcohol, for MeOH use pure methanol.
a note on the failures: waited for amalgamation to take off (same point of reference as i use with the MeNO2 al/hg - h2 bubbles evolving from solution at a decent rate, al foil is getting dull and some pieces begin to float, the EtOH or MeOH starts to turn cloudy) and then i add the oxime. after adding the oxime everything is fine, amalgamation is still taking place, then i add the glacial acetic acid and as soon as the glacial acetic acid is added the amalgamation slowly winds down and dies. the common factor here is with all the successful reactions i had used external heat to pre-heat the flask. everytime i had a failure where the GAA killed the amalgamation were times i did not use any external heat at all. going back over Oerlikon's posts, he didn't use external heating either. Oerlikon's attempts were at a scale of ~8-25g oxime, all of which failed due to no external pre-heating. all my attempts were around 10g oxime, give or take a few grams and experienced the same result.
so here's a quick procedural write-up on how the events take place for a successful al/hg using some external pre-heating:
*put 3-neck RBF in a water bath and toss a large stirbar in the RBF. charge your RBF with MeOH (or EtOH if you prefer), H2O and HgCl2. attach a reflux condenser to middle neck and stopper the side necks. turn on stirring on and wait until HgCl2 is dissolved.
*once HgCl2 is dissolved, begin feeding ice cold water through the reflux condenser and turn on the hotplate and heat the water bath to 55-60C
*once the desired water bath temp is reached then turn off your hotplate. you can remove the water bath at this point but i just leave it in place so that i can toss ice cubes in it to make it cool the RBF if necessary. unstopper a side neck and add the al foil balls in through that neck. since the MeOH/EtOH has been pre-heated, the amalgamation will take off very quickly. instead of waiting 15-20+ minutes for the amalgamation to progress enough for it to be ready for addition, with the pre-heating to 55-60C it will take off to that point within 1-3 minutes, so have everything necessary for the remainder of the reaction already weighed out and ready for addition because once the aluminum is added you won't have time to weigh out anything. i use a 10 molar eq of Al and GAA in relation to oxime per antibody
*once the amalgamation is ready (very fast with pre-heating, 1-3 minutes), unstopper a side neck and add the oxime then add the GAA, then re-stopper that neck.
*upon adding the oxime and GAA, the al/hg which take off very vigorously very quickly. the most intense part of this reaction is the first 10 minutes after addition of the oxime/GAA, with emphasis on the first few minutes. the MeOH/EtOH will get incredibly thick and turn into a thick gel just as antibody says. you'll add a small amount of MeOH/EtOH to return it to a liquid consistency as needed. for most people, stirring will fail and i have to resort to swirling the flask by hand. during the first 10 minutes i also keep an eye on the water bath thermometer, as the RBF gets hotter it will heat up the water bath temperature as well. i just keep an eye on the water bath thermometer and if i see the temperature of the water bath raising above 60C then i toss a couple ice cubes into the water bath.
*from here on out just keep an eye on it, keep the water circulating through your reflux condenser ice cold, add a small amount of MeOH/EtOH as needed if the solution gets too thick and gel-like, add a couple ice cubes to the water bath if necessary (this is most likely to only occur during the first 10 min's), swirl flask by hand if stirbar is stuck. the time frame of events in relation to a ~10g oxime scale is that the first 10 minutes are the most intense, then it continues at a steady/easy pace for just under an hour, then it will steadily cool down from that point. Once the reaction is complete and has started cooling off you can either reflux for 3 hours or you can let it stir overnight for several hours with no external heat. i'm not entirely sure what the bare minimum reaction time is without effecting yields but the 2 alternatives i mentioned are the 2 options i follow.
*when it's ready to be worked up, i add a 35% NaOH solution per RoidRage's trials he posted. i have previously added a more dilute NaOH solution but i prefer the 35% NaOH solution even though it's overkill. the benefit to the 35% NaOH solution is that the work-up seems less emulsion-prone and separation is much faster/easier during the extractions.
*from here on out you just work it up per normal: extract, wash, a/b, gas or titrate, recrystallize.
a note on the failures: waited for amalgamation to take off (same point of reference as i use with the MeNO2 al/hg - h2 bubbles evolving from solution at a decent rate, al foil is getting dull and some pieces begin to float, the EtOH or MeOH starts to turn cloudy) and then i add the oxime. after adding the oxime everything is fine, amalgamation is still taking place, then i add the glacial acetic acid and as soon as the glacial acetic acid is added the amalgamation slowly winds down and dies. the common factor here is with all the successful reactions i had used external heat to pre-heat the flask. everytime i had a failure where the GAA killed the amalgamation were times i did not use any external heat at all. going back over Oerlikon's posts, he didn't use external heating either. Oerlikon's attempts were at a scale of ~8-25g oxime, all of which failed due to no external pre-heating. all my attempts were around 10g oxime, give or take a few grams and experienced the same result.
so here's a quick procedural write-up on how the events take place for a successful al/hg using some external pre-heating:
*put 3-neck RBF in a water bath and toss a large stirbar in the RBF. charge your RBF with MeOH (or EtOH if you prefer), H2O and HgCl2. attach a reflux condenser to middle neck and stopper the side necks. turn on stirring on and wait until HgCl2 is dissolved.
*once HgCl2 is dissolved, begin feeding ice cold water through the reflux condenser and turn on the hotplate and heat the water bath to 55-60C
*once the desired water bath temp is reached then turn off your hotplate. you can remove the water bath at this point but i just leave it in place so that i can toss ice cubes in it to make it cool the RBF if necessary. unstopper a side neck and add the al foil balls in through that neck. since the MeOH/EtOH has been pre-heated, the amalgamation will take off very quickly. instead of waiting 15-20+ minutes for the amalgamation to progress enough for it to be ready for addition, with the pre-heating to 55-60C it will take off to that point within 1-3 minutes, so have everything necessary for the remainder of the reaction already weighed out and ready for addition because once the aluminum is added you won't have time to weigh out anything. i use a 10 molar eq of Al and GAA in relation to oxime per antibody
*once the amalgamation is ready (very fast with pre-heating, 1-3 minutes), unstopper a side neck and add the oxime then add the GAA, then re-stopper that neck.
*upon adding the oxime and GAA, the al/hg which take off very vigorously very quickly. the most intense part of this reaction is the first 10 minutes after addition of the oxime/GAA, with emphasis on the first few minutes. the MeOH/EtOH will get incredibly thick and turn into a thick gel just as antibody says. you'll add a small amount of MeOH/EtOH to return it to a liquid consistency as needed. for most people, stirring will fail and i have to resort to swirling the flask by hand. during the first 10 minutes i also keep an eye on the water bath thermometer, as the RBF gets hotter it will heat up the water bath temperature as well. i just keep an eye on the water bath thermometer and if i see the temperature of the water bath raising above 60C then i toss a couple ice cubes into the water bath.
*from here on out just keep an eye on it, keep the water circulating through your reflux condenser ice cold, add a small amount of MeOH/EtOH as needed if the solution gets too thick and gel-like, add a couple ice cubes to the water bath if necessary (this is most likely to only occur during the first 10 min's), swirl flask by hand if stirbar is stuck. the time frame of events in relation to a ~10g oxime scale is that the first 10 minutes are the most intense, then it continues at a steady/easy pace for just under an hour, then it will steadily cool down from that point. Once the reaction is complete and has started cooling off you can either reflux for 3 hours or you can let it stir overnight for several hours with no external heat. i'm not entirely sure what the bare minimum reaction time is without effecting yields but the 2 alternatives i mentioned are the 2 options i follow.
*when it's ready to be worked up, i add a 35% NaOH solution per RoidRage's trials he posted. i have previously added a more dilute NaOH solution but i prefer the 35% NaOH solution even though it's overkill. the benefit to the 35% NaOH solution is that the work-up seems less emulsion-prone and separation is much faster/easier during the extractions.
*from here on out you just work it up per normal: extract, wash, a/b, gas or titrate, recrystallize.
I imagins many would find your results and reasoning useful, so Go Hard Gypsymon 
