What is the chemical equation between phenol and ferric chloride?

Answer 1

We use Ferric Chloride (FeCl3) in the lab to test for the presence (or in some case absence) of phenols, although some enols will also yield positive results. The OH (hydroxy group) which is attached directly to an aromatic nucleus (Benzene, for example) is detected by the Ferric chloride. It is important to note that alcohols do not undergo the reaction. Phenols will typically yield dramatic purple,blue,red or green color as an indication of a positive test. FeCl3 will also indicate the presence of aliphatic acids (that is, non-aromatic organic acids, such as Acetic acid) turning the solution a yellow color. Aromatic acids will test as a beige-tan color. Enols will also show a characteristic yellow color. It is also important to understand that not all phenols will test positively in the presence of the FeCl3 reagent. A good example of this is in highly hindered phenols which do not yield positive tests. However, a negative test is not completely conclusive, so other tests can be preformed to verify the absence of a phenol (such as NMR and IR spectroscopy) We use Ferric Chloride (FeCl3) in the lab to test for the presence (or in some case absence) of phenols, although some enols will also yield positive results. The OH (hydroxy group) which is attached directly to an aromatic nucleus (Benzene, for example) is detected by the Ferric chloride. It is important to note that alcohols do not undergo the reaction. Phenols will typically yield dramatic purple,blue,red or green color as an indication of a positive test. FeCl3 will also indicate the presence of aliphatic acids (that is, non-aromatic organic acids, such as Acetic acid) turning the solution a yellow color. Aromatic acids will test as a beige-tan color. Enols will also show a characteristic yellow color. It is also important to understand that not all phenols will test positively in the presence of the FeCl3 reagent. A good example of this is in highly hindered phenols which do not yield positive tests. However, a negative test is not completely conclusive, so other tests can be preformed to verify the absence of a phenol (such as NMR and IR spectroscopy)

Answer 2

An iron-phenol complex is formed. FeCl3 + 6C6H5OH = [Fe(OC6H5)6]3- + 3H+ +3Cl- Most phenols (though not all) answer this test.

Answer 3

The chemical equation is:
FeCl3 + 6 C6H5OH = H3[Fe(C6H5O)6] + 3 HCl

Answer 4

FeCl3 +C6H5COOH