[joemok]

From Whiki, i see that only aldehyde or ketone have reactions with 2,4-dinitrophenylhydrazine.
It explains the inactivity of carboxylic acids, amides, and esters by resonance.
How about acid chloride and acid anhydride? They seem not to be resonance stabilized.

[FeLiXe]

first: you do have a weak +M from the Cl in an acid chloride and from the O in an anhydride

second: with acid derivatives you'd expect a substitution (product hydrazide) and not a condensation (leading to hydrazone)