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ScienceSquirrel
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| Quote: | Originally posted by kclo4
Sweet!
I wish I had a use for phenol, this thread is making me want to make it.
I wonder if chlorobenzene could be produced from phenol? That would make me very happy 
--I wouldn't be to surprized if chlorobenzene was produced by refluxing anhydrous phenol while bubbling anhydrous Hydrogen chloride Into it? Along
with a lewis acid probably, such as Zinc chloride, which I would produce in situ from zinc metal.
Does anyone have an idea how to make chlorobenzene?
[Edited on 2-8-2008 by kclo4] |
Chlorobenzene cannot be made from phenol.
Chlorobenzene can be made by reacting benzene with chlorine in the presence of aluminium chloride.
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kclo4
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That is sad
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Klute
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I would rather use bicarbonate as a base, phenol does react with carbonates to some extent....
Phenol very quickly takes a amber/orange colour from oxidized byproducts upon standing, and only pretty pur phenol is colorless. Be very carefull,
phenol is a very toxic compound, spilling an aqueous solution on your hands can kill you in a few hours.... It also readily sublimes.
Phenol can be usefull for lots of stuff, it can be formylated to salicylaldehyde for example, which is a very important precursor for coordiantion
chemistry ligands, forming complexes with Fe, Ni, Cu, etc
Being highly actiavted, it can also be pretty easily ring-alkylated, nitrated, etc
\"You can battle with a demon, you can embrace a demon; what the hell can you do with a fucking spiritual computer?\"
-Alice Parr
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ScienceSquirrel
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<u>Preparation of acetylsalicylic acid from Aspirin tablets BP and hydrolysis to salicylic acid</u>
Rationale
Careful reading of the insert in the box revealed that they contained aspirin 300mg and lactose, starch and talc as excipients, each tablet weighed
0.36g.
Hence it was decided to dissolve the aspirin in cold sodium carbonate solution, filter to remove the talc and starch and then precipitate the
acetysalicylic acid with hydrochloric acid.
Hydrolysis with sodium hydroxide and precipitation with hydrochloric acid would produce salicylic acid.
Experimental
Acetylsalicylic acid
Sodium carbonate (2g) was dissolved in deionised water (25mL) and five aspirin tablets were added. After gently stirring for 10 minutes they dissolved
to yield a faintly cloudy solution. The solution was filtered and the filter washed with deionised water (25mL). 8M hydrochloric acid (5mL) was added
dropwise to the filtrate with gentle stirring. The suspension was cooled in ice and filtered and the crude solid was washed with 25ml of iced water.
The solid was suspended in deionised water 15ml and heated to boiling, it was allowed to cool to RT and then cooled in ice Yield 1.2g, 80% mp 134 C
lit 135 C
Salicylic acid
The crude solid prepared in the method above was suspended in deionised water (14ml) and a solution of sodium hydroxide (2g) in deionised water (7mL)
was added. The solution was boiled for 15 minutes and then allowed to cool for 5 minutes. Hydrochloric acid (8mL) was added dropwise and the
suspension was cooled in ice. The crude salicylic acid was filtered off and washed with ice water (25mL). The crude solid was suspended in deionised
water (15mL) and heated to boiling, slow cooling to room temperature and cooling in ice yielded silky needles (0.9g 75%) mp 159-160 C lit 159 C.
Conclusion
This is not an economic way to prepare salicylic acid but it produces nice crystals in a good yield and would be a cheap way to practice some chemical
techniques. The tablets are 15p for a packet of 16 out my way and the cost of the other consumables is small.
[Edited on 9-8-2008 by ScienceSquirrel]
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