simple experiments

[jordehwa]

Hi i love inorganic chemistry and have been doing it for a while. But i'm starting to get interested in organic chemistry, I just dont know were to start i dont have any advanced glassware or stuff like that. So can some post some simple organic chemistry experiments for me to do? Thanks

[Horza2002]

Ester hydrolysis is an esay experiment to do. Simple get an ester, stir it with hydroxide overnight and then work up the reaction. The work up should be easy and you can seperate the resulting acid and alcohol very easily simply by washes. For this experiment you would only need a flask, two containter, hydroxide and some organic solvents.

 

E.g. Do the reaction and after it has finsihed, add a lot of water. Extract with an organic solvent and you'll have seperated your alcohol out. Now acidify the aqueous layer and your carboxylic acid should either crystalise out of the water or form a gum that you can then extract with another organic solvent.

 

 

Another simple experiment I did as a 1st year undergraduate was extract natural product from nutmeg and extract citric acid from orange's.

 

Heres what you could do to isolate citric acid. Basically, you deprotonate the citric acid with Calcium hydroxide to give calcium citrate. This is soluble in hot water but not in cold. So you add the calcium hydroxide to hot orange juice in water, then cool it down with ice, filter it and you'll have calcium citrate. Once that is done, dissolve the calcium citrate back up into hot water, add a dilute acid that will give you citric acid and calcium sulphate (which is insoluble and you can simply filter to remove) and this will leave your citric acid in the water which you can then evapourate to give you citric acid. If you cant to check the purity, the melting point of citric acid is 153oC; the closer you are to this value, the purer your sample is.

[jordehwa]

Ok thanks i will try that.

 

Also is there anything that can be made with alcohols and HCl? I'm asking cuz alcohol is cheap and i have lots of HCl

[Horza2002]

The reactions you can do will mainly depend on which alcohols you have. You could try these reactions I've picked because they should, in theory, be easy to do without specalised equipment:

• Dehydration reaction - if you relux your alcohol with the acid (this will require a secondary or tertiary alcohol and may take a while as HCl might not be strong enough, you usually use sulphuric acid for this reaction), you will get an alkene
  
• Esterification - so the reverse of one of the experiments I suggested above, have your alcohol and a carboxylic acid together with a catalytic amount of acid
  
• Epoxidation - if you have a 1,2-diol you could try and make an epoxide by heating with acid (WARNING: epoxides are very reactive towards nucleophiles are therefore carcinogenic); not sure this will work very well as the water you remove could simply attack the epoxide under the acidic conditions to give back the starting material
  
• Acetal - you could attempt to make an acetal by reacting your alcohol with an aldehyde or a ketone (vanilla is a commonly found aldehyde) and a drop of acid
  
• Oxidation - you could try oxidisng you alcohols to carboxylic acids. Primary alcohols will go to the corresponding carboxylic aicd where as secondary will go to the ketone. Tertiary alcohols won't be oxidised.
  

 

I've attached a PDF file showing what could happen.

Alcohol reactions.pdf

Edited February 19, 2011 by Horza2002

[jordehwa]

Ok thanks for the ideas

[mississippichem]

Ester hydrolysis is an esay experiment to do. Simple get an ester, stir it with hydroxide overnight and then work up the reaction. The work up should be easy and you can seperate the resulting acid and alcohol very easily simply by washes. For this experiment you would only need a flask, two containter, hydroxide and some organic solvents.

 

Isopentyl Acetate is a great ester to hyrdrolyze at home. It is an easily hydrolyzable ester that has a very distinct "banana" smell. So when the smell begins to disappear, you know that your ester is bring hydrolyzed.

 

I recommend this or something similar as the often the limiting factor in conducting organic chemist at home is not having any spectrometers or HPLC to analyze products with. Inorganic chemistry often gives you color cues, organic chem is often not so kind to the home experimenter.

Edited February 20, 2011 by mississippichem

[Horza2002]

Yes, that is why I suggested ester hydrolysis...the vast majority of easily avaliable ester have a characteristic smell to them that disappears during the reaction