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smuv
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Help: Failed chloromethylsulfonyl chloride Prep
I have twice attempted to synthesize chloromethylsulfonyl chloride from 1,3,5-trithiane, both times with failure. A process known to literature
entails chloronating 1,3,5-trithiane in an aqueous solution (sometimes with AcOH co-solvent). I am attempting to modify the procedure by generating
Cl2 and Cl+ in situ from TCCA in an acetic acid medium.
I will post my experimental procedures below, I hope some of you might chime in with your wisdom. I would really like to get this to work without
having to go through the hassle of a chlorine gas generator.
Experimental
ca. 40% formaldehyde solution
40g paraformaldehyde (OTC product dyed blue)
60mL Water
2 spatula tips NaOH
Everything was combined in a 500mL erlenmeyer and allowed to stir with heating. After about 15 minutes, everything had dissolved. The solution was
allowed to cool for 15 minutes and nothing precipitated out.
1,3,5-trithiane
Formaldehyde solution prepared above
100g Sodium thiosulfate
100mL 31.45% HCl solution
To the above prepared solution (at ca. 40c) the thiosulfate was added with stirring, after a majority of it had dissolved the hydrochloric acid was
added. At first nothing happened, then after about 30-60sec a very finally divided precipitate formed. Within another minute or so, the solution
became so thick with precipitate the stirbar froze. The solution was allowed to stand for ca. 15 min and was vac filtered, with the filtrate used to
complete the transfer. A light blue (from dye in the paraformaldehyde) finely divided powder was obtained. The yield was about 80g of a somewhat wet
product (note: the weight is way to much for this to just be finely divided sulfur).
A portion was mixed with methanol (at ca. 10c) and not much if any dissolved. A sample of the powder with strong heating on a metal plate with a
butane torch did not melt even with strong heating (it just slowly decomposed), however on direct heating with the flame burned with a blue yellow
flame. The same test with sulfur produced a red liquid which on prolonged heating ignited. A crude mp test showed a mp ca. 210c but since the
product is damp and plastery it is hard to determine where/when it melts.
Attempted chloromethylsulfonylchloride prep
Preface: BE CAREFUL! TCCA is a wicked oxidizer!!!
14g Trithiane from above
60g TCCA (93% pure)
50ml AcOH
50ml Hydrochloric acid (31.45%)
To a 500mL Erlenmeyer, in an ice bath, the trithiane was added followed by the AcOH. The TCCA was added in portions at first I did this with stirring
but it caused a lot of chlorine to be evolved, so I turned the stirring off and poured all of the tcca in (do this WITHOUT stirring if you value your
lungs). After standing for a few minutes, slow stirring was started, and allowed to proceed for a few minutes; chlorine was slowly evolved. Next
50mL of HCl was added dropwise at such a rate that not much Cl2 was lost to the atmosphere (ca. 2 hours). After addition everything was stirred for
about 2 more hours and allowed to stand for 14 hours.
The contents were vac filtered and the filter cake was washed with ca 100ml of water. The filtrate was homogeneous and therefore the synthesis was
deemed a failure.
The first time I did this was a COMPLETE failure, I was going to add the AcOH to a mixture of TCCA and trithiane (dry powders). While I was waiting
for the AcOH to thaw, a slowly escalating exothermic reaction between TCCA and trithiane ensued that released a good bit of Chlorine.
Discussion
I have posted my referance for the trithiane prep and 2 chloromethylsulfonyl chloride preps below.
I can't help but have some doubt as to whether I am actually dealing with trithiane, or if I just have a mix of finely divided sulfur with some other
crap.
With the chloromethylsulfonyl chloride prep, I am thinking I should just do away with adding the HCl to the AcOH mixture since this mix is an
excellent source of Cl+ as is, I think the HCl only drives out the chlorine. I am considering attempting this again with a suspension of trithiane
and TCCA in water and slowly adding AcOH dropwise. After addition I plan to just let the thing stir overnight.
Anyone have any input on how to get this to work?
Refs
J. Pract. Chem. 1908, 77, p. 367.
(trithiane prep)
J. Org. Chem., 1940, 05 (2), 81-85
(chloromethylsulfonyl chloride prep in AcOH)
J. Prakt. Chem. 1964, 23, p. 38.
(chloromethylsulfonyl chloride prep, Cl2 generated in place from chlorate)
"Titanium tetrachloride…You sly temptress." --Walter Bishop
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Klute
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Very interesting topic! I had never heard of this preparation, it seems it can be very usefull, starting from readily available materials!
I would think your problem would surely come from adding TCCA directly in the mix... producing Cl2 in a closed system, and gassing it directly in the
AcOH mixture is a easily done thing, not tedious at all, and you don't get bothered by Cl2 if you work correctly (I did several chlorinations,
including S2Cl2 preparation this way, with no hood and no problems or exposure to Cl2).
The cyanuric acid could very well react with the formed chloromethanesulfonyl chloride, and various ways, or with intermidiates, etc... I really
wouldn't take short cuts here, just to avoid working with Cl2... chances are ClCH2SO2Cl is worse than Cl2 anyway!
I would encourage you to tried the reaction again with dried Cl2, this reaction is analogous to the preparation of alkanesulfonyl halides from Bunte
salts, disulfides, etc, where H2O/AcOH is very often used. Most of the time Cl2 is passed until the green color subsist, indicating excess Cl2, and
thesulfonyl chlorides precipitate out when solid. There are several articles dealing with these procedures in the ref forum, if you really can't
locate them I can try and find them again. I think they ahve been mentionne din other threads on the preparation of sulfonyl chlorides and
chlorination of sulfur compounds in general.
Keep up the good work! This really is facinating! Good luck with futur reactions!
\"You can battle with a demon, you can embrace a demon; what the hell can you do with a fucking spiritual computer?\"
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smuv
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First thanks for the response. I have kept up with the chlorination of bunte salts (in fact this was my inspiration).
I may try the direct chlorination to get a feel for the reaction, but the whole point of doing this would be to try something that can easily be
scaled up to a large scale. No one wants to work with mols of chlorine.
Edit: drying the Cl2 is unnecessary as water is needed in this reaction.
Edit edit: you are right klute cyanuric acid probably reacts with the chloromethylsulfonyl chloride. I cant beleive I overlooked this!
[Edited on 12-16-2008 by smuv]
[Edited on 12-16-2008 by smuv]
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grind
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I agree with Klute. In the presence of TCCA side reactions are likely. Following the original procedure and using Cl2 gas is the safe way. Another
very convenient way is the procedure with HCl and KClO3.
And I think you should purify your trithiane, i.e. by crystallization from AcOH.
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smuv
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Is trithiane soluble in AcOH? I have found very little data about this compound.
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grind
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In your first reference article is a note:
Glacial acetic acid is a suitable solvent for crystallization of this compound. Benzene too.
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smuv
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Oh thanks, I missed that, I can't really read german.
"Titanium tetrachloride…You sly temptress." --Walter Bishop
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Nicodem
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Thanks for sharing your interesting experience.
Quote: | Originally posted by smuv
The contents were vac filtered and the filter cake was washed with ca 100ml of water. The filtrate was homogeneous and therefore the synthesis was
deemed a failure. |
Unfortunately I currently have no time to go trough the references posted, but I can not go by without saying that there is a serious flaw in the
logic of your cited sentence above. Chloromethylsulfonyl chloride should have a considerable water solubility and might just as well be miscelable
with water/AcOH. Its predicted logP is less than that of n-butanol but more than isopropanol, hence on the border of water miscelability.
Also, at the first glance both the use of acetic acid and HCl seem obsolete for this reaction. I can't see any role they might have. I could
understand that you used AcOH as cosolvent, but what is HCl doing there? It seems to have no other role but to waste your TCCA by reducing it to
chlorine which escapes out anyway. I would suggest to simply oxidize with TCCA in water suspension. There forms some HCl during the oxidation that
will prevent the hydrolysis of the sulfonyl chloride product by making the medium acidic. Cyanuric acid can not react with the product, at least no
more than water can.
[Edited on 17/12/2008 by Nicodem]
…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)
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Sauron
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You may find the following three preps from Org Syn useful for comparison.
I have combined these into a single pdf
sym-trithiane from formaldehyde in HCl treated with H2S
Direct chlorination of trithiane -> ClCH2SO2Cl not a great yield
Direct bromination of trithiane -> BrCH2SO2Br better yield
Purification of the crude trithiane is also described.
Hope this helps
Oh, BTW the halomethylsulfonyl halides are very potent lachrymators to take care.
[Edited on 17-12-2008 by Sauron]
[Edited on 18-12-2008 by Sauron]
Attachment: trithiane.pdf (250kB) This file has been downloaded 2476 times
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Sauron
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PS
The mp of the crude trithiane from the orsyn prep is well over 200 C and the mp of same after purification is sharp and over 240 C.
So there is not much chance of mistaking trithiane for precipitated sulfur. Just dry your product and take an mp.
It takes 9 mols Cl2 to chlorinate and oxidize 1 mol trithiane to 3 mols (theory) chloromethylsulfonyl chloride. In practice the yields are no better
than fair. Still the reagents are cheap. I would forget about TCCA and stick with direct elemental chlorination if I were you.
[Edited on 18-12-2008 by Sauron]
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smuv
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I used the acetic acid because the chlorination with the highest yields that I found was done in AcOH. On the other hand, this could be because AcOH
transiently forms AcOCl which is a good Cl+ donor...just as TCCA is. The HCl, I agree was unnecessary, I will save you my flawed reasoning at the
time.
@Sauron, I cleaned a small sample of the trithiane up by boiling in AcOH and cooling followed by boiling in isopropanol. I would not call this a
recrystallization as not much product dissolved in either. I will do a mp later today.
Also the stoichiometry you have given is disputed, details are given in the JOC paper I posted.
Thank you for the mp, the question is can my corn oil bath get to 240c gracefully...
Stay tuned...
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Sauron
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Both of those Org Syn preps involving direct halogenation of trithiane are a whole lot fresher (1969 and 1993) than the JOC citation (1940) and both
involve the eminent Leo Paquette as either submitter or checker.
Anyway the dispute you refer to is that the JOC author states that 1 mol trithiane gives 2 mols chloromethylsulfonyl chloride when treated with 7 mols
Cl2. This actually more halogen intensive not less...compared to 3 mols product from 9 mols Cl2. So this only underscored my point that this takes a
lot of chlorine or bromine to do the job.
I'll keep an open mind but if I were you I'd put more faith in the JOC paper only after you can replicate it.
Anyway the TCCA procedure is not supported in any of the refs. So if your trithiane is kosher then the TCCA is probably the problem.
[Edited on 18-12-2008 by Sauron]
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Ebao-lu
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Indeed, interesting reaction!
In the paper No2(J. Org. Chem., 1940, 05 (2), 81-85) it is mentioned:
Quote: | The question arose, at what stage in the above reactions scission of the
sulfur-methylene bond occurred. In order to determine whether the
oxidation proceeded first to the sulfone stage, sulfonal and di-n-butyl
sulfone were treated in the manner mentioned above. Both compounds
were obtained from this and even more drastic treatment unchanged.On
the other hand, butane sulfonyl chloride was formed from dibutyl sulfoxide.
Spring and Winssinger (6) obtained similar results with diethyl
sulfoxide. Thus it may be said that the breaking of the sulfur-carbon
bond occurs before the sulfone stage of oxidation is reached, but may take
place after the formation of the sulfoxide. |
I wonder, what is the mechanism of C-S scission. The sulfone inertness in comparison to sulfoxide may be explained by the abscence of an electron
pair, that sulfoxide possesses(sulfur in sulfoxides is well- alkylated by alkylhalides). So 1st that comes to mind is: Chlorine molecule probably
forms a complex-like intermediate with sulfoxide (or less oxydized compound), that further undergoes rearrangement with C-S breakout. Also, it may be
2nd route of non-synchronous addition of Cl+ to sulfur resulting in [R2ClS=O]+ and releasing of carbocation (either free, with further addition of
Cl-, or via Sn2 reaction with Cl- as nucleophile).
I guess, the 1st route is more preferable, because i've never heared of Cl+ agents could break C-S bond, otherwise, they are known to easily oxidate
sulfoxides to sulfones(at least hypochlorites). Then the role of excess of HCl is also clear, it should inhibit the HOCl and Cl+ formation (also it
inhibits the sulfurylchloride hydrolysis)
Quote: | The acetic acid-water solution
of the compound was sometimes saturated with gaseous hydrogen chloride previous
to the addition of the chlorine; this gave a slightly higher yield of the alkane sulfonyl
chlorides. |
That means, that the usage of chlorine substitutors like TCCA maybe problematic because of 2 reasons - they may not break the C-S bond and they may
oxidize sulfoxide to sulfone that can not react further. So i think the best option would be dropwise addition of TCCA to the solution containing
HCl, AcOH, tritian and water, with stirring. Actually, what was the procedure in that paper where they generated Cl+ from chlorate insitu?
unfortunately i dont know german..
As for tritian, it is a bit different subj, here the scission of C-S bond may be also hydrolitical, and the formation of CH2Cl may be caused by
concentrated HCl as well (anyway, who knows!), so maybe here Cl2 substitutors would also do..
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smuv
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I took the mp a few times, I am getting strange results. At about 190-200c the sample starts to wet and looks like its about to melt, but then starts
to brown somewhat and by 240c it seems to for the most part sublime away. I have done this with both slow heating and quick heating.
I guess I don't know what conclusion to come to. It is certainly not sulfur (mp), certainly not paraformaldehyde (smell) and it definitely not an
inorganic salt. On the other hand it does not dissolve in methanol as the German paper I posted states it should, and even on boiling does not
dissolve appreciably in acetic acid...I just don't know.
Part of me wants to say screw it and make more attempts at chloromethylsulfonyl chloride, however if what I have is not trithiane, I would just be
wasting my time.
Please no one tell me to make it from hydrogen sulfide...
"Titanium tetrachloride…You sly temptress." --Walter Bishop
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Ebao-lu
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Just looked throughout J. Org. Chem., 1940, 05 (2), 81-85. Chlorine breakout of C-S bond is not obligatory at all. Only in case of simple dailkyl
sulfides and sulfones it is unavoidable.
Merkaptals are at first step transformed into dialkyldisulfides with aldehyde release, so there is no need of C-S bond chlorination, and i quess Cl+
agents would also work. But in case of tritian, if the author's supposed mechanism is not a hasty conclusion, Cl+ agents will face C-S bond once
again.
PS(offtopic) I see, here TCCA is a very popular item, many people on the forum use it..
Is it sold as usual bleach/antiseptic in US? I'm sure, it can be used as a good, ready to use explosive, and comperatively sensetive. Where does
FBI/police look, i wonder?
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Sauron
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Org Syn does offer some salternatives
From CS2
From ethyl isothiocyanate
From potassium thiocyanate
In each case by reaction with Zn?HCl
From methylene iodide and alcoholic sodium hydrosulfide
Plus the process you don't want to hear about.
Citations in paper posted above.
KSCN may be best
MeI2 readily available from iodoform as described in a recent thread
You won't want to mess with ethyl isothiocyanate ("mustard oil") and you may not be able to buy CS2 depending on where you are.
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Ebao-lu
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2 smuv: I also think, that first you should be sure that it's tritian. Could you please translate the original procedure from german (maybe you made
some violations), or you have posted the original one?
Probably your tritian is easily sublimable because it is not pure. These admixtures may have catalyse its decomposion into thioformaldehyde (imho)
[Edited on 17-12-2008 by Ebao-lu]
2 Sauron
In the past, nitrogen trichloride was also a common chlorinator.. i dont compare it with NCl3, but still there is N-Cl bond. (sorry, i see the carbon
is +4 there, it can not be a "fuel" as i first thought) But in mix with some organic materials it will definitely be explosive.
[Edited on 17-12-2008 by Ebao-lu]
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vulture
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Can we keep this on topic and avoid double posting please?!
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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Sauron
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@smuv
clearly there's something wring with the trithiane, so either with the J.prakt Chem prep or your execution of it.
How about trying again and this time use the inverted extraction procedure with benzene recommended in Org.Syn.?
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grind
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The KClO3-method:
Suspend 13,8 g trithiane in 500 ml 37% HCl. Stir and cool with water during the portionwise addition of 40,9 g KClO3. Mixture becomes yellow and later
a yellow oil separates. Stir for 5 hours, then add the mixture to ice water and extract with ether. Wash the ether solutions with dilute
NaHCO3-solution, then with water, dry with Na2SO4. Remove the ether by distillation to obtain a slightly yellow oil which distills at 15 mm vacuum at
70°C. You get a colourless liquid with a pungent odor.
"Purification of Laboratory Chemicals" includes the purification of trithiane: crystallized from acetic acid.
Try to use more solvent (AcOH) for crystallization and filter the hot solution to get a pure product. If this isn´t working for your product, you can
consider it as very impure or the preparation failed completely.
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Ebao-lu
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Thanks for the translation of KClO3 method. I think, that with TCCA it should be done in the same way
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smuv
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Let it be known: The forum has a PM feature, USE IT!
I have ordered a commercial formalin solution, as I want to start from pure reagents. When the formalin arrives I will re-make the trithiane. I have
posted below another reference, which uses crude trithiane made from formalin and hypo directly in the synthesis of chloromethanesulfonyl chloride (if
someone wants to translate, be my guest, as my German is too rough to do so).
Ber. 1952, 85 p.456
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Formatik
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Quote: | Originally posted by smuv
I have ordered a commercial formalin solution, as I want to start from pure reagents. When the formalin arrives I will re-make the trithiane. I have
posted below another reference, which uses crude trithiane made from formalin and hypo directly in the synthesis of chloromethanesulfonyl chloride (if
someone wants to translate, be my guest, as my German is too rough to do so).
Ber. 1952, 85 p.456 |
Chloromethanesulfonyl chloride: 1.) To a conc. aq. solution of 250 g sodium thiosulfate, 150 ccm formalin solution and 150 ccm conc. hydrochloric acid
is added. After good stirring, the solution is heated to boiling, where a white crystalline mush of trithioformaldehyde results, flocculating in
nearly theoretical yield. 70g trithioformaldehyde is suspended in 350 ccm glacial acetic acid and 70 ccm H2O. This suspension has a strong Cl2-stream
lead through it, and is then cooled intermittently with water so that the temperature doesn't rise too strongly. When nearly everything has gone into
solution, some water is added, and then without cooling anymore at temperature of about 40 deg., Cl2 is lead into it for about 5 hours. The
chlorine-saturated solution is allowed to stand overnight, then the chloromethanesulfonyl chloride is precipitated out with ice-water, and then this
is dried over Na2SO4, and distilled in a vacuum. After only having distilled off for a bit, a very pure and uniform boiling product goes over.
Colorless oil, Bp.27: 82 deg., Bp.750: 173-174 deg. (little decomposition).
2.) Into a solution of 10 g paraformaldehyde and 50 ccm formalin in 100 ccm conc. hydrochloric acid, at 60-70 deg., H2S is lead in, preferably under
pressure. For a time of about 4-5 hours. Trithioformaldehyde precipitates out. This is not isolated, but Cl2 is lead into the mixture at -15 to -20
deg. for about 3 hours. Where the temperature can be allowed to reach up to room temperature. The precipitated chloromethanesulfonyl chloride is
separated and further processed as above.
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Sauron
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Commercial trithiane looks to be about $2 a gram 97% purity and ref. mp (lit) given as 215-220 C which is apparently nowhere near as pure as the
Org.Syn. product after reverse benzene extraction.
If the procedures from sodium thiosulfate work, which certainly sounds like it from the 1952 Ber. reference, as well as the older J.Prakt.Chem., then
this is certainly a lot more convenient prep than having to resort to a cylinder of H2S (ugh) or a H2S generator. s-Trithiane has uses beyond making
halomethyl sulfonyl halides, so this is very welcome.
A few years ago I wanted to do this the Org.Syn. way and went so far as to put together a pair of 2 liter tall cylinders with 45/40 joints on top and
fitting them with adapters and 29/42 jointed inlet/outlet heads from Pyrex gas washing bottles, attached to fritted glass ended tubed cut to go to
bottoms of the cylinders. I was going to charge these with formalin and HCl (Conc) and connect them in series and bubble in H2S, in a hood, but as I
had to wait on hood I never got around to it.
Now I will try the thiosulfate method instead. The cylinders can go back to being graduates and the gas washer heads can go back to their original 500
ml bottles.
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smuv
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Crystals sending mixed messages...
Product recrystallized from ca. 10% AcOH 90% i-PrOH(don't ask). The blue color is due to the dye in the paraformaldehyde
Tried to take a Mp, crystals dont melt they just decompose. This is becoming frusturating!
Thanks Formatik and Grind for the translations...these are for you:
[Edited on 12-18-2008 by smuv]
"Titanium tetrachloride…You sly temptress." --Walter Bishop
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