uemura (Hive Photographer)
04-25-02 01:25
No 300989
      much more uuuuuuuuuuu     

Foxy, not too high to calculate...smile

But Uemura is,... thanks foxy, uemura is still too tired to play around with variables. Uemura is sure that there is around a piece of SW you can feed in all the variables you want to calculate. Just take a simple example:


x P2O5 + y PCl5 + z_input --> a POCL3 + b output_


Here we are lucky, Take x=1  y=3 and a=5 (of course z=b=0). Here you have a set of equations like:

x (2 P + 5 O) + y (P + 5 Cl) =
(2 x + y) P + 5 x O + 3 y Cl ==
a P + a O + 3 a Cl

or


(P)  2 x +  y == a
(O)  5 x      == a
(Cl) 5 y      == 3 a

which is a set of an integral equation system with 3 equations and three variables, solutions are seeked within the range of positive integral numbers. this is also called a diophantic equation. (For details see S.L.Borevcs, L.R. Safarevics, Number Theory, Birkhäuser, 1966 )

If you haven't started with PCl5 but with PCl3, then you would have to add an additional variable, say u * Cl2 (It still seems you know about chemistry, because you haven't added u * He2).


u Cl2 + x P2O5 + y PCl3 + z_input --> a POCL3 + b output_


which is now again a diophantic equation (4 vars, 3 eqs!!!) as


(P)  2 x +  y == a
(O)  5 x      == a
(Cl) 3 y + 2u == 3 a


with the obvious (smallest integral solution!!!) solution x=1, y=3 ,u=3  and a=5.

In case you know the additional input and output z_input, b_output is zero (i.e. your are a good chemist to know what you need and what you get out), then at least you know the number of variables to deal within the diophantic equations. If not, then you are in trouble.... Uemura thinks you get a feeling what he is looking for in general. Either you are a genius chemist or a good mathematician, but in the latter one you nevertheless need to know the number of variables you deal with..

Anyway, looking at the pot with the crude TMP after destilleation of the MeOh, another salt precipitated, it is white, is it now Cu(I)Cl or just NaCL. Two more variables.......


Jesus, why didn't Uemura stick with what he learned....
 
 
 
 
    Antoncho
(Official Hive Translator)
04-25-02 06:23
No 301098
      More data     

Our beeloved Chemistry Lover Diafrag of HyperLab recently scanned and uploaded that very article to his site http://chemlover.narod.ru. There are some points in it that could bee helpful to the future generationswink:

1) The optimal rxn time (they say) is 50 C, but it is absolutely uncrucial - like 25 C is good (173 hours for MeOH) - 100% yield.

2) Lower alcohols are converted into TAlkP's - although EtOH gives about 33% triethylphosphite as a byproduct (again, at RT, 246 hrs).

3) Higher alcohols are converted to dialkylphosphates - but they react further to TAlkP's if the water formed is azeotropically removed. Again, some TAlkP-ites are formed as byproduct.


4) There is actually a table summarizing the rxn kynetics at RT for different alcohols - i am too as-busy-as-a-beesmile to type it in, read it in the original at http://chemlover.narod.ru/articles/article5.djv

5) They state the rxn equation to bee:
NaOH2PO + 4 CuCl2 + 3 ROH ----> 4 CuCl + NaCl + 3 HCl + H2O + (RO)3PO4

6) BUT you know what - "....cuprous chloride formed is re-oxidized by air to cupric chloride..."  so they actually perform the rxn (at RT and long time) in ambient atmosphere , with molar concentrations of the reagents being actually 1,14 g/mole NaH2PO2 and 0,74 g/mole CuCl2.
It also suggest a possible explanation, as well as a possible tremendous improvement for Half-A-Pint's DMS synthesis (BTW, Uemura, earlier in this thread you say that your attempts to make DMS failed - what did you mean? Did you try the CuCl2 method?)

7) Finally, cupric bromide cannot bee substituted for chloride in this reaction.



Antoncho
 
 
 
 
    uemura
(Hive Photographer)
04-25-02 10:18
No 301174
      Deeper insight...     

Antoncho,

Thanks a lot for the deeper insight... Uemuras observations now make sense. He hasn't however smelled any HCl during the run, perhaps it stayed in the MeOH?

BTW, Uemura, earlier in this thread you say that your attempts to make DMS failed - what did you mean? Did you try the CuCl2 method?)

No, uemura hasn't tried the CuCl2-DMS synthesis yet. Up to now he only tried the get TMP, no DMS yet.
Carpe Diem

 
 
 
 
    UTFSE
(Hive Bee)
04-28-02 05:54
No 302386
      us p     

Check these out.

BTW these are precursors for nerve gas precursors and in particular VX.

us5710307  process for the production of trialkyl phosphites
us2636048  method of producing trialkyl phosphate esters
us2410118  method of producing trialkyl phosphate esters
us4714771  process for preparing halogenated trialkyl phosphate esters
us1844408  production of phosphoric acid esters of aliphatic alcohols
us2005619  esters of acids of phosphorus
us3068269  process for producing trialkyl phosphites
us2905705  process for the manufacture of trialkyl phosphites
us1028384  process for preparing trialkyl phosphites
us1408744  process for producing esters
us2848474  method of producing and recovering trimethyl phosphates




OTEECEE & meeeee!!!!
 
 
 
 
    psyloxy
(Hive Addict)
08-22-04 03:49
No 526669
      old pictures     

Here's the pics that are now missing in Post 265013 (uemura: "Methylation with (CH3)3PO4", Chemistry Discourse).







--psyloxy--
 
 
 
 
    Rhodium
(Chief Bee)
08-31-04 23:00
No 528576
      ../rhodium/chemistry/me3po4.html     

Thank you! I have reinserted those pixtures into the appropriate post and added Uemuras writeup to the document at ../rhodium/chemistry /me3po4.html

The Hive - Clandestine Chemists Without Borders
 
 
 
 
    Kinetic
(Hive Bee)
09-04-04 21:32
No 529571
      Methylations with trimethyl phosphate
(Rated as: good read)
    

Acid Catalysis of Phenol Etherifications With Trialkylphosphates

Patent US2683784

Example 2
Seventy-one grams of phenol (0.75 mole), 40 grams of trimethylphosphate (0.286 mole) and 0.5 gram of p-toluene sulfonic acid were heated together. The reaction was proceeding slowly so 1.0 gram more p-toluene sulfonic acid was added and the reaction proceeded rapidly. The anisole was distilled out of the reaction mixture through a short column; B. P. 155-158o C., yield 75 g. (92 per cent).