The Hive > Newbee Forum
#128 Methyl-J MBDB
psyloxy:
3 N means : normality, the concentration of protons (hydrogen ions) in the solution is 3 mol / L
what is a mol ? 1 mol = 6.022 . 1023 molecules. http://gemini.tntech.edu/~tfurtsch/scihist/avogadro.htm
Now we need to find out, how many protons HCl donates to the solution. HCl __> H+ + Cl-
As you can see 1 mol of hydrogen chloride gives 1 mol of protons in solution (dissociation). Therefore a 3N solution is 3M. H2SO4 gives 2 protons, therefore a 3N solution of sulfuric acid would be 1.5M.
What does 3M mean. M is for molarity and specifies the concentration of a compound by mol / L. Just like normality but now it is not restricted to only protons (H+) anymore.
How to prepare a 3M soln. of HCl ?
What we need to find out is how much of a solution, of which is known that 36% of the weight are HCl, needs to be mixed with water to leave a concentration of 3 mol / L.
We've got the weight m , we need the amount of substance n.
M = m / n ;; molecular weight = mass / amount of substance. The question is how many grams do 6.022 . 1023 molecules (1 mol) weight ?
If you put amount of substance as 1, the molecular weight can be calculated from the atomic weights of its constituents, found in the periodic table of the elements.
H has an atomic weight of 1.0079 u
Cl has an atomic weight of 35.453 u
http://en.wikipedia.org/wiki/Atomic_weight
So one molecule of HCl weights 36,4609 u and thus one mol = 36,4609 g
Yeah, back to the solution we wanted to prepare.
3 mols will weight 109.3827 g. This much is in (109.3827 g / 36) . 100 = 303.84 g of a 36% HCl (the strength of concentrated HCl). To get the volume of those 303.84 g we need the density (which is dependant on temperature and usually given for 20°C if not specified differently). That is 1.18 g/mL. http://ptcl.chem.ox.ac.uk/MSDS/acidsbases.html .
So the volume will be 303.84 g / 1.18 g/mL = 257,49 mL.
We're almost there. Since we want a concentration of 3 mol / L those 257,49 mL need to be mixed with water, until a total volume of 1000 mL is reached.
BTW: this also works exactly the same way with bases like NaOH, where N (normality) would specify the concentration of hydroxide ions (OH-) in the solution as mol / L.
mixing 15mL 36% HCl with 45mL should give a 2,913 N solution, with 38% HCl it would be
3,075 N. So it sounds about right.
Hope that helped anyone...
--psyloxy--
tryin:
So then, this is how I see this synth working out.
Use this method from Rhodium - piperonal from pepper
Next, you make 1-(3,4-methylenedioxy)-2-nitrobutene using - Post 533253 (starlight: "there is probably a better way to do this", Newbee Forum)
Then reduce using Shulgin's method for Methyl-J. By using Al/Hg and MeAm.HCL being that you already have it for above process.
Extract and clean up to arrive at - 2-methylamino-1-(3,4-methylenedioxyphenyl)butane hydrochloride (METHYL-J or MBDB)
Is this a correct way to go about it, or am I seriuosly off-track? If I am off-track, please let me know where I am going wrong.
Rhodium:
No, you cannot use the procedure outlined in Post 533253 (starlight: "there is probably a better way to do this", Newbee Forum)
Only these are proven to work satisfactorily: Post 536518 (Rhodium: "Piperonal & 1-Nitropropane", Newbee Forum)
tryin:
Thank you Rhodium for clearing that up for me.
Could one use Toulene or Xylene instead of benzene in the Post 536518 (Rhodium: "Piperonal & 1-Nitropropane", Newbee Forum) method?
indole_amine:
Yes, benzene is mostly replaced with toluene these days, due to its toxicity. It is just mentioned very often because it was the standard solvent in the earlier days of chemistry. Todays use of benzene is almost solely limited to applications in chromatography, and as reagent in certain syntheses. There is no case where you can't substitute benzene for toluene solvent AFAIK.
indole_amine
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