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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: 1101 on December 04, 2010, 07:39:38 PM

Title: Can anyone recommend reducing agents that can be commonly purchased?
Post by: 1101 on December 04, 2010, 07:39:38 PM
Are there any reducing agents that would be capable of reducing a carboxyl group to an alcohol group and that one can actually buy in a hardware store or something? For instance wikipedia says ascorbic acid (vitamin c) is a reducing agent, but would it be strong enough to reduce a carboxyl group?
Title: Re: Can anyone recommend reducing agents that can be commonly purchased?
Post by: MissPhosgene on December 04, 2010, 08:50:12 PM
lithium aluminum hydride
Title: Re: Can anyone recommend reducing agents that can be commonly purchased?
Post by: 1101 on December 04, 2010, 09:55:47 PM
lithium aluminum hydride

LAH is a reducing agent sure, and it would work in this case, but would i be able to find it in a hardware store or something?
Title: Re: Can anyone recommend reducing agents that can be commonly purchased?
Post by: saden99 on December 04, 2010, 10:01:50 PM
At a hardware store? I don't know...but yes Lithium aluminium hydride with H2O (adding the H2O after the LiAlH4 has reacted of course) or Sodium borohydride with methanol should work.



Ascorbic acid is not going to be strong enough but either of the above mentioned should be as they are metal polyhydrides and highly effective at reducing the carboxyl oxygen. LiAlH4 is a tad bit stronger than NaBH4 and more difficult to work with since it can react violently in any amount of water. In fact, you often leave it in a dry solvent like diethyl ether to make sure it remains dry.


I suggest using sodium borohydride unless you find a need to reduce an ester.



Edit: Wanted to add that you could either look online at the hardware store website or call and ask. They would usually have a catalog of their inventory and would be able to easily check. I doubt they have either lithium aluminium hydride or sodium borohydride there. Also consider the need for other reagents (such as the drying agent for LAH or methanol for NaBH4).
Title: Re: Can anyone recommend reducing agents that can be commonly purchased?
Post by: MissPhosgene on December 04, 2010, 10:13:04 PM
You will not find either in a hardware store.
Title: Re: Can anyone recommend reducing agents that can be commonly purchased?
Post by: 1101 on December 04, 2010, 11:32:16 PM
So is there any physical store (a hobby store maybe?) that would sell reducing agents? I've checked online and they're quite expensive or only available in extremely large amounts.
Title: Re: Can anyone recommend reducing agents that can be commonly purchased?
Post by: MissPhosgene on December 05, 2010, 11:06:28 AM
If you want to find them go through Aldrich or another chemical supplier. Since NaBH4 and LiAlH4 react with water to produce hydrogen gas, they need to be packaged and shipped following certain protocols. I highly doubt you will find them anywhere other than a university, industrial, or supplier stockroom.

If you live near a university, you might ask them if they have a bottle. Sometimes there are chemicals on shelves which were opened in the 1970s that nobody uses or wants.