Hey guys! If we replace an atom of oxygen with an atom of sulfur
in a molecule of highly toxic and suffocating phosgene gas,
we will get an orange-red highly toxic fuming liquid called thiophosgene.
And this reagent is the highlight of today's video.
Unlike Sigma Aldrich, that wraps their reagents in special absorbing cloth,
Acros Organic delivers their chemicals filled with special absorbing powder that resembles filler for cat's toilets.
So, thiophosgene is a suflur analogue of phosgene.
It's an orange-red liquid with strong smell,
and despite it being a strong electrophilic reagent, it's still less active than its oxygen analogue phosgene
Thiophosgene is a volatile liquid, in moist air thiophosgene gives fumes and is oxidized to phosgene and sulphuric acid
A Wikipedia article about thiophosgene says that it forms a head-to-tail dimer upon irradiation with UV-light
I decided to check that and exposed a thiophosgene sample to both UV-light with the longest wavelength
and UV-light with medium wavelength.
Then I exposed the sample to the sun, and tried to focus sunlight on it using a magnifying glass.
I didn't notice any change, although a few days later
I discovered that my sample did dimerize into colorless solid dimer
It's partially orange because it's a little bit dirty due to the presence of original thiophosgene.
Phosgene qualitative reaction is its interaction with aniline water, where it forms diphenylurea precipitation.
Much like phosgene, thiophosgene forms diphenylurea precipitation in this reaction.
Thiophosgene is fairly stable towards cold water. It reacts very slowly with water at room temperature
Thiophosgene hydrolyses in boiling water to form hydrogen chloride and carbonyl sulfide
The latter forms carbon dioxide and hydrogen sulfide in reaction with water
To prove the formation of hydrogen sulfide I used Lead(II) nitrate solution, that forms black precipitation in reaction with it
The reaction of thiophosgene with chlorine forms perchloromethyl mercaptan
This is why we can see the color change from orange to pale yellow
Thiophosgene reacts with potassium superoxide extremely violently
The reaction of pyridine with thiophosgene causes ring scission.
It seems this reaction must be performed in the presence of a solvent,
since a direct interaction between these reagents leads to tarring
To neutralize spilled thiophosgene or to get rid of its remains in the laboratory, ammonia solution is used
Its reaction with thiophosgene is not violent and it leads to the formation of thiourea
However, liquid ammonia reacts with thiophosgene violently
Thanks for watching guys, hope you enjoyed this video! And many thanks to my patrons that support this channel
and make these unique chemical reactions come to life!
See ya in the next video