Sammy!!!i'm in debt to you for
ever, ever-ever!!!
You finally DID it! It is unfuckingbelieveable, but true!
Needless to say, catechol is a sensitive compd and if you can mehylate it w/NaMeSO4 the same method will rather certainly work on hydroquinone and the aldehydes.
I won't translate these russian links since they contain no other info than already posted. They will bee very much appreciated by my fellow russian bees, though. The only thing the english abstract doesn't mention is the prep'n of NaMeSO4: "...265 g of methylsulfuric acid is neutralized w/235-237 g of 42% NaOH soln. with stirring, the temp. should bee around 28 C."
The pure alkylsulfuric acids themselves are very conveniently prepared in almost quantative yield by a method submitted by our dear comrade Foxy2 - the one with EtOH/H2SO4/NaSO4 - see
Post 216461
(foxy2: "Ethyl hydrogen sulfate", Chemistry Discourse). There's also a US patent # 3,024,263 found by - guess whom
- our admirable PolytheneSam, naturally, which describes a similar process, but using NaHSO4 (hydrate) and alcohol.
SWIM have tried the 1st method and is firmly certain that it works exactly as described. Well, Foxy2 didn't give the exact procedure, just the outline, so SWIM just used his common sence and the info he grasped from the said US patent, so it's not optimized, but anyway here's what he did:
100 cc (2 mole) of 92% H2SO4 were dripped into 100 cc (2.2 mole) of methanol in ice bath w/good stirring. You can skip all this precautions at this stage but you do need to chill the rxn well. The resulting mixtr had a reddish tint. Then in it was dropped 80 g of powdered anhydrous Na2SO4. This is probably an overkill as Na2SO4 forms a decahydrate at below 32 C. Just to bee sure. The mixtr was then heated in boiling water for 10 mins - again just to bee sure (Foxy2's proc. mentioned RT, but in the US patent as well as in the proc. on Rhodium's heating was employed) and cooled to below RT in cold water, with frequent shaking. SWIM left it at RT for some time, periodically giving it a shake, to ensure all the water has been absorbed. It was then vacuum filtered through a paper filter, the Buchner closed w/a lid to exclude atmospheric moisture, and kept in a freezer overnight.
Thus obtained methylsulfuric acid was a viscous off-white liquid with density of 1,32 g/cm3 and amounted to 100 ml (1.2 mole) - much of it left in the filtered sulfate - a good source of vacuum (SWIM's is very bad) and less Na2SO4 probably should bee used to improve the yield.
This acid was dripped with good stirring and chilling in ice bath into a slight molar excess of NaHCO3 in some water - a little more than enough to cover the soda. The mixtr actually thickens as neutralization proceeds. Thus obtained homogenous fine paste was evap'd on a steam bath aided w/a hair dryer - now
note this the alkylsulfates (ethyl too) obviously have mp lower than 100 C - at least they will never look dry while hot and solidify upon cooling.
Thus obtained salt was further dryed in exicator for 2-3 days over CaO.
A 5 g sample of the salt was dissolved in a minimum of hot water and reacted w/sat'd CaCl2 soln. The precipitate was filtered, washed, flame-dried to give 1,5 g of CaSO4*1/2H2O which corresponds to NaMeSO4 content of approx. 71% -
!
These procedures were also performed with ethanol instead of methanol by a russian bee named
Vitsh with whom SWIM worked on this project hand-in-hand. His results were essentially the same except he got his ethylsulfate content only 50% - and Antoncho strongly believes it was because of his inverted neutralization technique - he added sat'd Na2CO3 soln to the acid.
Now this will bee obvious to many but still allow me some notes on the issue of neutralization.
The
very clever 
authors of the russian patent don't mention if the acid was added to the alkali or backwards. From the precise wording of their phrases Antoncho guesses that they did the latter.
Now, it is a well-known fact that alkylsulfuric acid salt are stable, but the acids themselves exist in aq. solutions in equilibrium w/AlkOH/H2SO4, which is about fifty-fifty. This means the following: suppose during neutralization the soln. has become acidic. A molecule of an alkylsulfuric acid hydrolizes to H2SO4 , which, unlike the former, is a two-hydrogen (what's the correct term in English?) acid and reacts with two molecules of NaAlkSO4, producing
two molecules of AlkHSO4, which in turn react with
four molecules of NaAlkSO4 and so forth - as you see, this rxn proceeds in geometrical progression - that is, FAST - and stops when the equilibrium point (~50%/50%) is reached.
Another empirical data comes from one more experiment of SWIM's - he dripped MeHSO4 into ice-chilled sat'd NaOH taking pH every now and then. SWIM was afraid to have leftover NaOH in his mixtr as nitromethane forms explosive salts with it. So the rxn accidentally got acidic for like not more than 2 mins and - voila! - he got his sulfate content that very 50%.
Oh gosh that's enough for now
Antoncho
