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Abigail
September 24th, 2006, 03:25 PM
I`ve converted something from Megas sites, chlorination of the alpha hydrogen in precence of red phosphorus. I would guess it can work with a alkohol instead a carboxylic acid. I belive you can get the upper mentioned compounds by this method.

4-Chloro-1-Butanol:
C4H10O, 108,56 g/mol, bp ~50°C
183 ml 1-butanol is mixed with 10 g red phosphorus in a 500 ml glass flask, connect the flask to a claisen and a reflux
condenser. Connect a thermometer to the adapter and a glass tube to the bottom of the mixture. Put the apparatus to a
sunny place that the flask can receive as much sunlight as possible. After that, a regular current of dryed chlorine is
bubbled through the flask for 12 hours. You can use a chlorine generator and two drying tubes with concentrated H2SO4 to dry the chlorine. To increase the yield the flask is short heated to 45 °C at the end of the reaction. Than the crude 4-chloro-1-butanol is removed from mixture by distillation above 50 °C. The distilate contains somewhat water and remainders of di- and trichloro-1-butanol. Maybe it will work when a few gramm of a anhydrous substance is added to the distilate bevor it purifyed by distillation.

1,4-Dichlorobutane:
C4H8Cl2, 127,01 g/mol, bp: ~155 °C
1,4-dichlorobutane can be prepared exactly as 4-chloro-1-butanol by 209 ml 1-chlorobutane and 10 g red phosphorus.

I don`t know i tinking correct, you can get a alkohol when a solution of potassium or sodium hydroxide
is stirred to the chlorinated substance, the mixture is heated for a while and the crude stuff is than distilled.

1-Butanol:
C4H10O, 74,12 g/mol, bp ~116-117 °C
May be it can prepared from 1-chlorobutane and 1 mol dilute potassium hydroxide solution.

1,4-Butanediol:
C4H10O2, 90,12 g/mol, bp: ~230 °C
1 mol of 4-chloro-1-butanol and 2 mol potassium hydroxide solution.

Does anyone have infos to the conditions to the process ? When this is correct, you can get easy 1,4-Butanediol from 1 mol of dichlorobutane and 2 mol of potassium hydroxide solution.

megalomania
September 26th, 2006, 09:40 PM
Now there is a topic near and dear to my heart, but first I must ask: how can you be certain you will get 4-chlorobutanol? You have adapted the procedure for chloroacetic acid. In theory I can see where you are going with this, but you are not replacing the alpha hydrogen with this reaction. The alpha hydrogen is on the C2, that is to say the carbon right next to the carbon attached to the hydroxyl. What you are reacting is the gamma hydrogen when using butanol. The mechanism for this reaction would also be quite different owing to the fact you do not have a carbonyl and its inherent stability.

I would conjecture all you will end up with is butyl chloride. Unless you are deriving this procedure from some sort of published literature source, in which case I will defer to the published procedure. That source would be?

Abigail
September 30th, 2006, 04:36 PM
Yes that`s right, the mechanism is quite different to the chloroacetic acid and yield a slight amount of some derivates but the phosphorus will help that only one hydrogen is chlorinated. I would guess the procedure will work correct.

I have found a process on a kind of chem supplier page many years ago, benzyl chloride in KOH/H2O will yield benzylalkohol.
May is ask a question, do you can found a reference to the mentioned procedure ?