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F334 ­ What's in a Medicine?

Carboxylic Acids and their Derivatives

Carboxylic Acids:

Contain the carboxyl functional group.
Their systematic names all end with ­oic acid.
The formula is often shorted to ­COOH
When two carboxyl groups are present the ending ­dioc acid is used.
When naming branched chain carboxylic…

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An example would ethanoyl chloride.




Amides have the functional group ­CONH




An example would be ethanamide




Acid anhydrides are another derivative




An example would be Ethanoic anhydride




The OH Group in Alcohols, Phenols and Carboxylic Acids

The OH Group:

Can occur in three different environments ­ alcohols, phenols and carboxylic…

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When a neutral iron (iii) chloride solution is added to phenol or its derivatives, a purple
complex is formed.
This test allows us to distinguish between alcohols and phenols.

Acidic Properties:

Alcohols, phenols and carboxylic acids are all weak acids.
They react with water to produce oxonium ion, for example:…

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The other product of the reaction is water.
The reaction can be reversed and the ester can be hydrolysed.
In this case a more suitable catalyst would be dilute sulphuric acid.

Making esters from a phenol:

Do not form esters in the same way as alcohols.
Will react with acyl…

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Therefore both reactions have a 100% atom economy.

Substitution reactions:

Involve replacing one group in a molecule with another.
There are always two products formed.
Therefore atom economy is always less than 100%.
The larger the Mr of the leaving group the lower the atom economy.

Elimination reactions:

Involved removing…

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The dichromate(VI) ion is reduced to Cr3+ in the reaction:
Cr2O72-(aq) + 14H+(aq) + 6e- 2Cr3+(aq) + 7H2O

Reactions:

Only aldehydes can be further oxidised with acidified potassium dichromate(VI) because of
the hydrogen atom on the carbonyl group.
They also react with Fehlings solution.
The aldehyde is oxidised to a…

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This is the Brnsted-Lowry theory.
Acids donate H+ to water in aqueous solution to become H3O+ (the oxonium ion)




An alkali is a base that dissolves in water to produce hydroxide ions
For example, sodium hydroxide, potassium hydroxide and sodium carbonate
Sodium carbonate produces hydroxide ions by the following reaction:…

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Indicators:

Acid-base indicators, such as methyl orange or phenolphthalein are themselves weak acids.
In order to behave as an indicator the conjugate acid and base forms of the molecule must
have different colours. In the case of methyl orange, the acid form is red and the conjugate
base is yellow.…

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Fragmentation




The molecular ion peak corresponds to the molecular mass of the compound being
analysed. It is the peak furthest to the right on the spectrum.
From the mass spectrum above, it is clearly evident that the ions which correspond to
the molecular ion (X+) are not the only ones…

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Eventually the masses that have been lost from a compound become familiar. For example,
28 is the loss of a C=O group, 77 for the loss of a C6H5 (benzene ring) etc.

Isotope Peaks:

Some elements have more than one naturally-occurring isotope. For example natural chlorine
consists of 75% 35Cl…

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Iyanu

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Very useful, thank you for the time and effort

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