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View Full Version : Would this work? (sodium chloroacetate)


FadeToBlackened
April 26th, 2003, 10:29 PM
After reading the fluoroacetate thread in battlefield chemistry, i began wondering if one could electrolyse sodium acetate in HCl solution to produce sodium chloroacetate (for nitromethane) ?

Einsteinium
April 27th, 2003, 12:57 AM
Sodium acetate will first react with HCl producing acetic acid and sodium chloride. What you get if you electrolyse this solution is chlorine gas, water and sodium chloride. If all HCl is consumed NaOH will also be produced. Chlorine gas may react with acetic acid through a radical reaction (heat or better, light-catalyzed) and this is the reaction that would produce chloroacetate. The reaction proceeds very well (sometimes too well) in the vapour phase. I think there are easier ways to produce chlorine than electrolysis for this reaction, for example HCl and bleach (NaOCl or Ca(OCl)2) reacts together and ultimatly produce chlorine gas. Dichloro and trichloro acetic acid may well be produced in larger amount than chloroacetic acid if you don't control the reaction thoroughly.

Marvin
April 27th, 2003, 04:58 AM
Dry HCl in glacial acetic acid will certainly work, and directly as the electrolysis produces chlorine radicals, not chlorine as the first step product. The chlorine radicals are the limiting step in light stimulated reactions, and here light and heat arnt required. Additional water, and salts are to be avoided, dry HCl is easy to make with conc sulphuric and salt. Unfortunatly, with any preparative electrochemistry you are limited by the very high value of the faraday, so high currents and long time periods are needed. In this situation you may as well generate just the chlorine electrochemically, and use this in the standard synth with potentially higher yeilds and avoiding cell problems like kolbe electrolysis of the organic acid...

jfk
April 27th, 2003, 06:07 AM
from what ive read the chlorine radicals bond togethor to form Cl2 at the annode (positive terminal), please tell me if im right/wrong

or were you meaning that the first step is formation of chlorine radicals, and the second step was the formation of chloreine gass at the annode ?

Einsteinium
April 27th, 2003, 03:33 PM
Chlorine radicals does bond together forming chlorine gas but they may also react with acetic acid instead as Marvin states, much chlorine gas will be lost though. Dry HCl in acetic acid without adding salt or water dosen't conduct electricity very much as the ionic mobility of protonated acetic acid is quite small. Also, if you don't separate your cells you will have the reduction of chloroacetic acid to acetic acid at the cathode, which make the overall process quite useless.

FadeToBlackened
April 28th, 2003, 08:06 PM
If one were to allow the acid to fully chlorinate (to CCl3COOH), would reaction with NaNO2 give trinitromethane?