Sciencemadness Discussion Board

Probable way to Cl2C=CH-OH

fludyoptasyphos - 2-4-2010 at 06:24

It's possible this synthesis of 2,2-dichloro-vinyl alcohol ?
the reaction
C2H2 + Cl2 --> C2HCl + HCl
C2HCl + HClO -->Cl2C=CH-OH
I know CH2=CH2 + HClO --> Cl-CH2-CH2-OH

[Edited on 2-4-2010 by fludyoptasyphos]

bbartlog - 2-4-2010 at 07:42

No. The triple bond in acetylene is not going to survive oxidation by elemental chlorine (that mixture looks borderline hypergolic :o ). With enough chlorine I would expect to get carbon tetrachloride and HCl (complete oxidation). Maybe under the right conditions you could limit it to oxidizing across the triple bond and get dichloroethylene but I don't see any references to such a synthesis and am skeptical that that would be feasible either.

[Edited on 2-4-2010 by bbartlog]

fludyoptasyphos - 2-4-2010 at 07:48

oh , mh, what is the steps to avoid C2H2OCl2 ?

CCl4 + CH3OH --- ? ---> CCl2CHOH

[Edited on 2-4-2010 by fludyoptasyphos]

[Edited on 2-4-2010 by fludyoptasyphos]

per.y.ohlin - 2-4-2010 at 08:36

Acetylene and chlorine is hypergolic. The reaction procedes as follows:
C<sub>2</sub>H<sub>2</sub>+Cl<sub>2</sub> --> 2C (amorphous) + 2HCl
I've heard of other reactions, producing various chlorinated hydrocarbons, but you're not going to get chloroethyne.
You have proposed this reaction in your second post:
CCl<sub>4</sub> + CH<sub>3</sub>OH --> Cl<sub>2</sub>CCHOH + HCl
I sincerely doubt this would work. The two reactants could react with light as a catalyst, but the products are chloroform, acetaldehyde and hexachloroethane [source].

Nicodem - 2-4-2010 at 10:30

Fludyoptasyphos, if a reaction does not make sense when writing its equation on paper, then it most likely makes no sense to real world either - that is why we have theory, to understand the real world. Always keep this in mind when writing down equations and always keep in touch with theory so you don't end up in fantasy.

2,2-Dichloroacetaldehyde (the stable form of your "Cl2C=CH-OH") can be prepared by chlorination of ethanol with Cl2. There were discussions on this forum and some references posted, mostly it being an intermediate in the synthesis of chloral (Cl3C-CHO), so UTFSE.