Question

Are Anhydrides highly reactive?

Answer 1

The reactivity of any group of molecule depends upon the stability the leaving group has i.e. more stable the leaving group more will be reactivity and vice versa.
And anhydrides are comparatively very less stable, so we can say that they are highly reactive.

Complete step-by-step answer: Let us know about the anhydrides and their reactivities;
Anhydrides are the chemical compounds which are obtained by the elimination of water molecules from certain other chemical compounds. This can be better explained by an example as follows;
CaO is an anhydride obtained from calcium hydroxide i.e. $Ca{{\left( OH \right)}_{2}}\rightleftarrows CaO+{{H}_{2}}O$
The anhydrides obtained from bases are known as basic anhydrides and those obtained from acids are known as acidic anhydrides.
Now, talking about the reactivities; the leaving group of the anhydrides are comparatively very much stable and that’s why they leave prominently leaving the remaining molecule less stable and hence more reactive.
Thus, the anhydrides are highly reactive.

Note: If we specifically compare, anhydrides to the esters then we can say that the former one is highly reactive than the next one; as in esters one oxygen atom needs to stabilise only one carbonyl group.
Also, the most common and important of the organic anhydrides is the acetic anhydride i.e. ${{\left( C{{H}_{3}}CO \right)}_{2}}O$ .