Procedure

First quickly crunch your pre-dried (oven, 300°C, 3 hrs.) dry MgSO₄ to pop corn shaped rocks in a mortar, sieve the powder out, and directly put the rocks under max. mixing in the Methanol/Methylamine mix and close the pot to let no water from the air in. Keep mixing for 10 minutes, then all the water will be taken up to the MgSO₄. Let stand and wait till all the MgSO₄ is on the bottom. Now quickly tap off the now DRY MeOH/MA mix in a 2L reaction flask and close that one. Wash directly your empty pot with lots of water, to remove the smell of methylamine so you can safely store it.

Now add the 200 ml (measure in beaker, neglect the free spaces) dry Silicagel beads (2-5 mm) and a magnetic mixer bar also in the 2L flask and close again. Keep 2L flask in Silicone-oil bath at 20°C. Silicone-oil only slowly warms up! Do not apply heat now, it's only meant as a cooling medium in this stage. Now add slowly via a dropping funnel the 138 gr P2P to the 2L flask under strong mixing. The temperature rises to 23°C during the (waterfree) Imine forming. The water from this reaction is taken up by the dried Silicagel! This takes 30 minutes. Let then mix for another hour. The reaction mix color changes from light yellow to coffee+milk color. Temp 23°C.

Stop mixing after this 1 hour and pour the fluid off into a 2L glas erlenmeyer with flat bottom and add a mixbar. The remaining Silicagel is washed 3 times with 50 ml dried (use silicagel) methanol, to catch the remaining Imine, and those 2 x 50 ml is also poured into the 2L erlenmeyer. Now put the 2L erlenmeier on magn.mixer, in a icecubes/methanol bath (-10°C) and start strong mixing. Put a Funnel on top of 2L erlenmeier, in rubber ring. Now start adding, every 5 min., a teaspoonfull (flat off!) of boro and wash in with minimum methanol. After every spoonfull, stopper the funnel loosely with a rubber stopper. This takes 2.5 hrs. Do not exceed a temp of more then 20°C! You can add the next spoon at ±8°C. Solution color is light clear orange/brown. Let mix in total for 8.5 h (could perhaps be lot less hours, do'nt want to know: time is not money!)

The total volume is ~1900 ml. Add then the mix to 5 L dest. water in a 10 L flask, under magn.mixing. The pH=12. Add then 500 ml DiChloroMethane (DCM) and mix strongly for 30 min. Let oil precipitate and a dark, honey-coloured layer of DCM+oil is on the bottom. Decant the waterpart with an aspirator + siliconetube. Fill the rest (water+DCM+oil) in a seperator funnel and tap off only the DCM+oil = 550 ml. (DCM b.p. 40°C). The leftover MgSO₄ and boro salts stayed nicely in the waterpart. Then dry the DCM+oil with some dry MgSO₄ and decant in 2L erlenmeier. Wash this MgSO₄ with some fresh, DRY DCM and add the DCM washings to the now dry DCM+oil. Total volume DCM+oil =1000 ml, colour is honey/red.

Start now bubbling this 1000 ml with HCl-gas, while 2L erlenmeier stands in icebath on magn.mixer and mix strongly. Check pH frequently, proceed until pH 6. Pour the now acidified 1000 ml in a 2 L evap.flask and put on Rotavap machine. Speed = 100 rpm, temp = 80°C, mode=p/auto, little vacuum=800 mbar, to hold the flask. After distillating off nearly all the DCM, suddenly the contents of the flask turns from dark honey colour to creamy milk color and it dries out to a round cake on the bottom. Remove the 1 L DCM, now in the collector flask, and hang that empty flask on again. Now put full vacuum on to remove the last traces of water.

Cleaning by 3 x recrystalization: Put MINIMUM quantity of hot (40°C) dry DCM (or dry 98+% Ethanol) in the flask until the last remains of the dry stuff dissolves, and add 4 x this DCM-quantity in the form of DRY acetone. Close with stopper and put 1 hr in freezer. A solid dirty-white crystal mass is formed with a layer of dark red fluid on top of it. Decant the fluid and repeat this step another 2 x and 2 Hrs. You have, the last time, snow white crystals. Dry Weight = 141.5 gram, close to quantitative yield.

You can eventually melt this crystal mass in a alu flatbottom pot on a heaterplate at 170-175°C. Then let this melt, very slowly, and do not go higher then necessary to melt it, or its starts smoking (you have your first quick-test then: enjoy!). Cool down to 150°C again, really slowly, 1°C/30 min. (regulate with your temp controller!), and you got dl-ICE, after you let it very slowly again cool down to room temperature (with a closed lid on it!, its hygroscopic!). Advantage: you removed all the water in this process!

You can better make the sulfate salt following Logicals method: Let 10% H₂SO₄/Ethanol mix acidifying a 1:4 mix of freebase Meth/Ethanol. This is not so hygroscopic. Filter and dry the crystals.