Page 75 - phytochemistry I - PharmD Clinical

• Borates (Boric acid esters).
• Phthalates (phthalic acid esters).
• Benzoates (Benzoic acid esters).
As a general rule primary alcohols react more readily with acid
anhydrides, than secondary alcohols, and tertiary alcohols are not
appreciably affected:

• 1ry alc + Phthalic anhydride Steam bath Phthalic acid ester
dil. benzene

This ester is extractable with sodium bicarbonate, and hydrolysis

regenerates the alcohols.

• 2ry alc + Phthalic anhydride 120-130°C

Phthalic acid ester

• 3ry alc + Phthalic anhydride No ester formation
(Dehydration Occurs)

Ester formation can be used for separation of a mixture of 1ry, 2ry and 3ry
alcohols.

3- Dehydration products:
Most 3ry alcohols are unstable and split off water, when reacted upon by
reagents generally employed in the preparation of alcohol derivatives.
Dehydration products may be useful for the identification of the 3ry alcohol.

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