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CuReUS
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the hunt for the reducing agent
i am trying to synthesise 2,4 diaminophenol from 2,4 dinitrophenol and the preferred reducing agent is sodium dithionite(Na2S2O4).The problem is,i
dont have any and have been trying to find a suitable substitute ,so it would be very helpful if you could correct my ideas and also suggest some of
your own
my ideas are:
1.hypo(Na2S2O3).this is a little silly i admit but hypo also gets oxidised to elemental sulphur(remember the double iodine/hypo titrations),and since
the mechanism for dithionate reduction is a free radicle S02 by auto-oxidation http://pubs.acs.org/doi/abs/10.1021/j100784a510
if we could generate a free radicle S02 ,we could be well on the right path(something similar to generating a N02 free radicle in vapor phase
nitration)
2.Zn/HCl -this reagent is old as time itself.although Sn/HCl and Fe/HCl reductions of nitro compounds are common,the horrible mess that we have to
clean up afterwards drives me nuts .Since ZnCl2 is soluble in hcl (i think) the
reaction mixture would be translucent throughout the reduction( i hope) and monitoring the reaction would be easier(the color change from
yellow(nitro) to colorless(amine),indicating that the reduction is complete.)
note:but since its diaminophenol wont the OH be acidic due to both the nitro groups and would zinc also react with it to liberate H2 rather than from
HCl
note:it is better to do the Zn/HCl reduction in ethanol/HCl mixture because the solubility of h2 in ethanol is 0.0072g/kg compared to 0.0016g/kg in
water.but if ethanol is used is there any chance of formation of ethyl chloride(as ZnCl2 will be formed which will act as a dehydrating agent
note:i came across a better reduction using Zn/NH4COOH from the hive http://chemistry.mdma.ch/hiveboard/chemistrydiscourse/000351...
as anyone ever done this before?
3.by passing S02 gas -a wild idea, i agree
4.by hypophosphorous acid(H3P02).-since the H is attached to a weakly electronegative P it can act as a reducing agent,worth a try
please look through my ideas and suggest better ones if possible
[Edited on 23-9-2014 by CuReUS]
[Edited on 23-9-2014 by CuReUS]
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gdflp
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Is the preferred reducing agent sodium dithionite Na2S2O4(the formula you gave) or sodium dithionate Na2S2O6(the name you gave)? Dithionite is
actually fairly easy to synthesize. Also, not criticizing you but, you can have hypophosphorous acid but not dithionite/dithionate? Where did you
buy it?
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CuReUS
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Quote: Originally posted by gdflp  | | Is the preferred reducing agent sodium dithionite Na2S2O4(the formula you gave) or sodium dithionate Na2S2O6(the name you gave)?
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.very sorry its sodium dithionite. | Quote: Originally posted by gdflp | | Also, not criticizing you but, you can have hypophosphorous acid but not dithionite/dithionate? Where did you buy it? |
i dont have it, the idea was just a shot in the dark.if someone suggested it,i could try to synthesise it
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gdflp
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Couldn't you just reduce sodium metabisulfite or bisulfite with zinc and filter off the Zn(OH)2 to yield a solution of sodium dithionite? You would
have to evaporate it carefully, but it shouldn't be too difficult. Another option if you live near a Wal-Mart(or another store that carries it) is
Rit Color Remover.
[Edited on 23-9-2014 by gdflp]
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CuReUS
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gdflp
i could try the reduction method,but would it give a good yield(i need around 40g of dithionite)
and please dont suggest buying sodium dithionite as it is not availaible.i repeat,buying it is completely out of the question
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violet sin
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16$ is completely out of the question?
50g
http://www.ebay.com/itm/SODIUM-DITHIONITE-50G-PURITY-87-ANAL...
19.80$ for 100g
http://www.ebay.com/itm/Sodium-dithionite-dihydrate-Sodium-h...
[Edited on 23-9-2014 by violet sin]
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Nicodem
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| Quote: Originally posted by CuReUS | | have been trying to find a suitable substitute ,so it would be very helpful if you could correct my ideas and also suggest some of your own
|
Hydrogenation over Pd-C at atmospheric pressure is obviously the most obvious choice and probably also the most amateur friendly. Anything else will
require a tedious isolation.
| Quote: | | 1.hypo(Na2S2O3).this is a little silly i admit but hypo also gets oxidised to elemental sulphur(remember the double iodine/hypo titrations),and since
the mechanism for dithionate reduction is a free radicle S02 by auto-oxidation http://pubs.acs.org/doi/abs/10.1021/j100784a510 |
"Hypo"? Where did that come from?
Na2S2O3 is sodium thiosulfate.
So, what is the reference for the reduction of nitroaromatics with thiosulfates? I don't remember ever seeing one, though I can imagine that under
certain conditions it might reduce some nitroaromatics. Though, probably not sufficiently practical.
| Quote: | | if we could generate a free radicle S02 ,we could be well on the right path(something similar to generating a N02 free radicle in vapor phase
nitration) |
Sounds like pure nonsense. Firstly, you probably mean sulfur dioxide which is SO2. The chemical symbol for oxygen is "O" and not "0" (zero)! Secondly,
SO2 is not a radical. While NO2 is formally a radical, SO2 is not. Thirdly, the article about the mechanism of
dithionite reduction of nitrophenol talks about the SO2- radical.
| Quote: | | note:but since its diaminophenol wont the OH be acidic due to both the nitro groups and would zinc also react with it to liberate H2 rather than from
HCl |
I can't see how could this affect the reduction.
| Quote: | | note:it is better to do the Zn/HCl reduction in ethanol/HCl mixture because the solubility of h2 in ethanol is 0.0072g/kg compared to 0.0016g/kg in
water. |
What relevance the solubility of hydrogen has on the reduction of your substrate? In this case, who cares what the solubility of a gaseous side
product is?
| Quote: | | but if ethanol is used is there any chance of formation of ethyl chloride(as ZnCl2 will be formed which will act as a dehydrating agent
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The conditions used for these reductions are not the same as those required for the nucleophilic chlorination of aliphatic primary alcohols. While
traces of ethyl chloride can always form in ethanolic HCl, this has no relevance to the reduction itself.
What makes you believe that method is any better than using Zn/HCl?
| Quote: | | as anyone ever done this before? |
Chemists generally tend to avoid applying obvious fiction in their work.
| Quote: | | 3.by passing S02 gas -a wild idea, i agree |
What is the reference for the reduction of nitroaromatics with SO2? Perhaps you confused it with H2S, which is occasionally used
for reducing nitroaromatics.
| Quote: | | 4.by hypophosphorous acid(H3P02).-since the H is attached to a weakly electronegative P it can act as a reducing agent,worth a try
|
Do you have a reference for a non-CTH or non-catalyzed reduction of nitroaromatics with H3PO2? I have only seen CTH reductions
with this reagents. (again, the symbol for oxygen is "O")
| Quote: | | and please dont suggest buying sodium dithionite as it is not availaible.i repeat,buying it is completely out of the question |
Interesting. Where on earth is sodium dithionite unavailable to the average consumer?
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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macckone
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| Quote: Originally posted by gdflp | Couldn't you just reduce sodium metabisulfite or bisulfite with zinc and filter off the Zn(OH)2 to yield a solution of sodium dithionite? You would
have to evaporate it carefully, but it shouldn't be too difficult. Another option if you live near a Wal-Mart(or another store that carries it) is
Rit Color Remover.
[Edited on 23-9-2014 by gdflp] |
Is there a good work up for purification from Rit?
Sodium metabisulfite is available from any brew supply
And zinc can be easily obtained from us pennies if
No other source.
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gdflp
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Not sure about the work up preparation. The MSDS claims it to mainly be sodium dithionite and sodium carbonate, with a small amount of disodium EDTA,
sodium silicate, geraniol and silica. My CRC claims sodium dithionite is slightly soluble in ethanol and sodium carbonate isn't, so dissolving in
anhydrous ethanol might work.
Attachment: MSDS_RITColorRemover.pdf (128kB)
This file has been downloaded 1079 times
[Edited on 23-9-2014 by gdflp]
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CuReUS
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| Quote: Originally posted by Nicodem |
| Quote: | it is better to do the Zn/HCl reduction in ethanol/HCl mixture because the solubility of h2 in ethanol is 0.0072g/kg compared to 0.0016g/kg in water.
What relevance the solubility of hydrogen has on the reduction of your substrate? In this case, who cares what the solubility of a gaseous side
product is? |
the more soluble the H2 gas is in the solvent,the longer it would stay dissolved and more product would get reduced.whats the point if all
the H2 just bubbles out of the container.2,4 dinitrophenol isn't that soluble in water or acid until it is reduced to amino
because the normal Zn/HCl reduction( https://www.erowid.org/archive/rhodium/chemistry/leminger.ht...)takes >12 hours compared to 2-5 minutes in the Zn/NH4COOH version
| Quote: | 3.by passing S02 gas -a wild idea, i agree
What is the reference for the reduction of nitroaromatics with SO2? Perhaps you confused it with H2S, which is occasionally used
for reducing nitroaromatics. |
i know about that reduction,but it is not applicable here because it will partially reduce only one nitro group to amino ,i want diamino
[Edited on 24-9-2014 by CuReUS] |
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Nicodem
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| Quote: Originally posted by CuReUS | | the more soluble the H2 gas is in the solvent,the longer it would stay dissolved and more product would get reduced.whats the point if all
the H2 just bubbles out of the container.2,4 dinitrophenol isn't that soluble in water or acid until it is reduced to amino
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Hydrogen does not reduce nitro groups in absence of a hydrogenation catalyst. It is the zinc that reduces the nitro group. The hydrogen is just a
reaction side product.
More than 12 h for the reduction under classical conditions and 2-5 min under fictional conditions? Are those experimental or fictional values? The
first does not fit to experience while the second is only realistic for the Indian laws of chemical kinetics.
| Quote: | | Quote: | | 3.by passing S02 gas -a wild idea, i agreeWhat is the reference for the reduction of nitroaromatics with SO2? Perhaps you confused it with
H2S, which is occasionally used for reducing nitroaromatics. |
i know about that reduction,but it
is not applicable here because it will partially reduce only one nitro group to amino ,i want diamino |
Like I already mentioned, I would like to read your reference about the SO2 based reduction, please.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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chemrox
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"The hydrogen is just a reaction side product." which hydrogen? In the Clemmenson you need the proton to break up the Zinc complex don't you?
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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Crowfjord
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Elemental hydrogen (H2) is a side product. A proton is indeed needed; but as I understand it, the proton is abstracted from an acid like
HCl or water after the election transfer (reduction) step is completed.
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CuReUS
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| Quote: |
| Quote: Originally posted by Nicodem | | Hydrogen does not reduce nitro groups in absence of a hydrogenation catalyst. It is the zinc that reduces the nitro group. The hydrogen is just a
reaction side product. |
but i always thought that the nascent hydrogen formed did the reduction ,if the
metal is doing the reduction,then why are Sn and Fe more commonly used than Zn(especially Sn) when Zn is way above them in the electrochemical
series(and dont say that Fe/Sn are cheaper,Fe may be but Sn is certainly not wont
Zn do a better job at reducing whatever it is you want to reduce?
| Quote: |
More than 12 h for the reduction under classical conditions and 2-5 min under fictional conditions? Are those experimental or fictional values? The
first does not fit to experience while the second is only realistic for the Indian laws of chemical kinetics. |
actually the truth is that i havent been able to get a proper reference on Zn/HCl reduction .the 12 h reaction time(shocked me too)
was mentioned in this https://www.erowid.org/archive/rhodium/chemistry/leminger.ht... .i would be very grateful if you could give the correct procedure for the Zn/HCl
reduction.and why are you so reluctant about the indian reduction,do you have something against the hive and its references
| Quote: | | 3.by passing S02 gas -a wild idea, i agreeWhat is the reference for the reduction of nitroaromatics with SO2? Perhaps you confused it with
H2S, which is occasionally used for reducing nitroaromatics. |
i know about that reduction,but it
is not applicable here because it will partially reduce only one nitro group to amino ,i want diamino
Like I already mentioned, I would like to read your reference about the SO2 based reduction, please |
i think i clearly mentioned that the SO2 gas was a wild idea  i just
thought that since H2SO4 was a reducing agent,SO2 might be too
and i didn't shoot down your H2S idea,i just said that i have come across several reaction involving NH4HS reduction(i think
H2S works similarly) in which only one nitro group gets reduced.after getting everyone's feedback about my ideas,i think the Zn/HCl or the
H2S is probably going to be my best bet
[Edited on 25-9-2014 by CuReUS]
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Crowfjord
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H2SO4 is an oxidant, rather, and usually only at high temperatures. Sulfur dioxide can be a reducing agent under some
circumstances, I think, but I don't remember seeing any reference I it being used to reduce organic molecules.
I think sodium sulfide (Na2S) would be a little safer than hydrogen sulfide, and just about as effective. I used it a few years ago to
reduce a tetranitro-phthalocyanine to the tetraamino derivative. I'll see if I can find the reference.
[Edited on 25-9-2014 by Crowfjord]
For some reason, I can't get electronic access even though my school has this particular issue of this journal on the shelves, but the reference I
used is:
Achar, B.N. (01/1987). "Synthesis and structural studies of metal(II) 4,9,16,23-phthalocyanine tetraamines". Polyhedron (0277-5387), 6 (6), p. 1463.
DOI: 10.1016/S0277-5387(00)80910-9
[Edited on 25-9-2014 by Crowfjord]
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Rabodon
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My fav to Reduce NO2-Groups is Zn/HCOOH in EtOH.
You can make a slurry of fine Zn powder (you can activate it using thinned aq. HCl is your powder is old) in EtOH and add 85% HCOOH in portions.
Reaction is very smooth unlike Al/Hg in IPA or LAH/THF. Good mechanical stirring is necessary to keep Zn in suspension - a good overhead stirrer is
necessary for reductions larger then 10-15g substrate, for small batches strong magnetic stirring can be sufficient. After addition of all HCOOH heat
a little further for 1-2h while still stiring to complete reaction. Workup is a charm, simply filter unreacted Zn, boil it down until Zn-formiate
starts to precipiate, let it cool slowly to room temperature giving very nice large white shiny flakes of Zn-formiate, filter, wash Zn-formiate
crystals with more EtOH, boil filtrate down again (and filter again if necessary), add aq. NaOH and extract free amine with solvent of your choice.
This method is using simple, basic, and dirt cheap chemicals, it gives very high yields (90%+ for most substrates), it's non toxic, doesn't produce
ugly exhaust fumes, and it's ultra clean and selective (doesn't deshalogenate and I guess also doesn't attack double bonds if the aren't very
activated).
Zn/HCl does also work in EtOH but it produces more side products (dark goo), especially if it get's too warm, while the HCOOH- way usually stays
completly colorless and clean. Yields with HCl are smaller aswell in ALL the cases I've tested and workup is less beautyful.
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CuReUS
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Rabodon,this method is fantastic ,i wish someone had given me the details of the prodecure before ,as i have already carried out the reduction using
Zn/HCl .the chemical i had to reduce was 2,4-dinitrophenol and it is extremely sensitive to air oxidation once it has been converted to the
diamino.but if the diamino is immediately put in dil HCl ,the salt is formed which is resistant to oxidation .so i thought that i would kill two birds
with one stone-by putting the dinitro(1.5g) in acid solution(10ml conc HCl +10ml water)and adding Zn granules(3g).the dinitro would get reduced to the
diamino that would simultaneously form the salt with HCl. in the beginning the dinitro wasnt that soluble in the acid solution but as the reaction
proceeded ,the solubility increased until it completely dissolved confirming that the reduction had taken place.i had expected to see a color change
from yellow(nitro) to colorless(amino) but that didnt happen and the color changed from light yellow to a tan color .but when i filtered the
solution(it had unreacted Zn granules) the filterate was exactly the same as described in the literature(slightly pinkish)
i didnt remove the ZnCl2 though (actually in standard metal/HCl
reductions such as Fe/HCl or Sn/HCl you can precipitate the Fe,Sn using Zn but to precipitate Zn you need a more electropositive metal such as Mg,and
the procedure is cumbersome ,not as easy as your method of just boiling it till Zn-formiate starts to precipitate.)
will that effect further reactions(i divided the filterate into two parts and did acetylation using acetyl chloride/pyridine for one and added
FeCl3 to the other half)
| Quote: | | Zn/HCl does also work in EtOH but it produces more side products (dark goo), especially if it get's too warm |
this is exactly what i was scared of (nicodem please take note) .initially i
foolishly assumed that the H2 evolved does the reduction and wanted to use ethanol as H2 was more soluble in alcohol than in the
water acid mixture,but nicodem cleared that misconception so i didnt use any ethanol in my reduction(thank you god and thank you nicodem) .but i have references that use isopropyl alcohol along with Zn/HCl
surprisingly the reaction did not become too warm at all(i could hold the beaker on my palm) and i didnt use any freezing mixture either so maybe i
have done something wrong (there were a lot of bubbles from the Zn granules though)
but why do you think HCl gives less yield,isn't it a stronger acid than formic acid,so wont that make it a better proton donor.
[Edited on 26-9-2014 by CuReUS]
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bbartlog
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HCl is acidic enough to cause miscellaneous side reactions in a way that acetic acid does not. Also the excess energy (Zn + HCl generates more heat
than Zn + HCOOH) probably contributes to the production of crap. Stronger is not the same as more selective.
The less you bet, the more you lose when you win.
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zed
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"Hydrogenation over Pd-C at atmospheric pressure is obviously the most obvious choice and probably also the most amateur friendly. Anything else will
require a tedious isolation."
Was this approach overlooked, because it wasn't the answer you were looking for?
This method is worthy of consideration. When Nicodem makes a suggestion, it is usually a useful suggestion.
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UnintentionalChaos
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What's wrong with stannous chloride or mossy tin in HCl?
Having worked briefly with 4-aminophenol (and 2,4-diaminophenol being even more sensitive), this stuff oxidizes like crazy. Even in acid solution.
Fortunately, the acid slows it down by keeping the anilines mostly protonated.
Any alkaline media is going to result in a big vat of black polyaniline tar or I'd suggest thiourea dioxide in aq. ammonia (or NaOH) which I have used
very successfully for luminol.
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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CuReUS
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| Quote: Originally posted by zed | "Hydrogenation over Pd-C at atmospheric pressure is obviously the most obvious choice and probably also the most amateur friendly. Anything else will
require a tedious isolation."
Was this approach overlooked, because it wasn't the answer you were looking for?
This method is worthy of consideration. When Nicodem makes a suggestion, it is usually a useful suggestion.
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i would have loved to use Pd/C or even lithium aluminium hydride but the problem is that they are not OTC,extremely difficult to work
with(LiAlH4) and ordering Pd/C will surely put you on Big brother's watchlist
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CuReUS
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nothing,its just that i had Zn lying around,btw would SnCl4 be colorless like ZnCl2
| Quote: | | Having worked briefly with 4-aminophenol |
did you synthesize it ,if so which route did you use? were you going to use it for making paracetamol?
| Quote: | | this stuff oxidises like crazy ,even in acid |
depends on the strength of the acid,1M H2SO4 or 2M nitric acid will keep the solution clear for days
| Quote: | | in alkaline solution,you will get tar,polyaniline... |
thinking about it now,i remember when i was acetylating it with acetyl chloride,the moment i put the pyridine(7 ml) into the diamino.HCl,the whole
solution became purpulish and a greyish white ppt formed.at that time i thought that it was because of the ZnCl2 and continued the
acetylation by adding acetyl chloride(7.5 ml).after the exothermic reaction was over ,the ppt has dissappeared and the solution has become a wine red
color.i heated the solution in a water bath for 5 minutes and kept it in freezer to crystallise(didnt have ice around)
now after reading your post on the effect of alkaline medium on diamino phenol ,i think i have just screwed up big time
[Edited on 27-9-2014 by CuReUS]
[Edited on 27-9-2014 by CuReUS]
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Rabodon
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Has anyone here had success using HCOOH + ammonium formiate or potassium formiate + Pd/C for any reduction?
There are some references claiming to get extremly high yields for NO2-Reductions.
My 10% Pd/C by Merck seems to be very overreactive with potassium formiate + HCOOH as hydrogen donor, producing only tar with the aromatic substrates
I've tried - I guess it's so strong it reduces the aromatic system in my case.
[Edited on 27-9-2014 by Rabodon]
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bbartlog
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What procedure are you trying to execute? There are no reducing agents in the chemicals you list, only catalysts and hydrogen donors, and furthermore
potassium formate seems like it would be needlessly alkaline, but without any mention of substrate, conditions etc. I can't tell whether you are
omitting details or actually trying to do something senseless.
The less you bet, the more you lose when you win.
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Rabodon
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| Quote: Originally posted by Rabodon | My fav to Reduce NO2-Groups is Zn/HCOOH in EtOH.
You can make a slurry of fine Zn powder (you can activate it using thinned aq. HCl is your powder is old) in EtOH and add 85% HCOOH in portions.
Reaction is very smooth unlike Al/Hg in IPA or LAH/THF. Good mechanical stirring is necessary to keep Zn in suspension - a good overhead stirrer is
necessary for reductions larger then 10-15g substrate, for small batches strong magnetic stirring can be sufficient. After addition of all HCOOH heat
a little further for 1-2h while still stiring to complete reaction. Workup is a charm, simply filter unreacted Zn, boil it down until Zn-formiate
starts to precipiate, let it cool slowly to room temperature giving very nice large white shiny flakes of Zn-formiate, filter, wash Zn-formiate
crystals with more EtOH, boil filtrate down again (and filter again if necessary), add aq. NaOH and extract free amine with solvent of your choice.
This method is using simple, basic, and dirt cheap chemicals, it gives very high yields (90%+ for most substrates), it's non toxic, doesn't produce
ugly exhaust fumes, and it's ultra clean and selective (doesn't deshalogenate and I guess also doesn't attack double bonds if the aren't very
activated).
Zn/HCl does also work in EtOH but it produces more side products (dark goo), especially if it get's too warm, while the HCOOH- way usually stays
completly colorless and clean. Yields with HCl are smaller aswell in ALL the cases I've tested and workup is less beautyful.
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Little addition, I forgot to mention that after filtration, before I'm boiling down, I'm adding a tiny splash thinned aq. HCl to lower the pH a
littler further, to inhibit amide formation and to recover amines from potentially already formed amides. Might be a placebo, as you're usually adding
aq. NaOH afterwards anyway which should recover the amides, at least slowly. One I forgot to add some HCl and only got ~80% instead of my usual 90%+,
but that might be a coincidence, as my educt was from a different purity. HCl excess might harm your product, you might end up with more goo, and my
suggested workup wouldn't work anymore, so only add a splash.
Another side note: Usual 90-96% EtOH works very well but MEK could theoretically cause N-(2-butyl) derivates as impurity in product. You can reflux
and destill EtOH over NaOH to remove the MEK prior use or add a little NaBH4 if you have before starting Zn and HCOOH addition (NaBH4 addition doesn't
harm yield at all) if you care. I don't know if IPA or MeOH are working as perfectly well as EtOH for this procedure, but they could be worth to try
them, as they are comming usually much purer when bought OTC and they are free of ketones.
| Quote: Originally posted by CuReUS |
but why do you think HCl gives less yield,isn't it a stronger acid than formic acid,so wont that make it a better proton donor.
[Edited on 26-9-2014 by CuReUS] |
It's my empirical data.
HCl a stronger proton donor for sure but in my experience simply also causes more side products. Don't forget you're using the HCl in large excess,
and heating/boiling chemicals in such a strong acidic solution is actually not what I would call very sensitive. Also other factors like EtCl
formation, worse soloubility of reactants due the water from the aq. HCl, the reactivity of ZnCl2, impurities like chlorine in technical grade HCl and
others might play a role.
For me HCOOH instead of HCl worked always better, yielding often perfectly clear and colorless amine straight after simple acid/base workup while the
HCl way always caused slightly to much lower yields and products which always cotained more or less visible goo, for some reactions sometimes very
much of it.
And workup by precipiating the beautyful Zn formiate crystals is such a charm for your eyes, it's worth to do it even without an substrate inside you
reaction mixture
[Edited on 27-9-2014 by Rabodon]
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