Acetanilide + P(O)Cl3, then hydrazine hydrate I think would work.

Transamidation to form the acetic hydrazide seems to be the most likely result.

Formation of the imidoyl chloride with OPCl3 or an equivalent such as the imidoyl triflate with triflic anhydride, followed by addition of hydrazine would be a better way of forming your desired system. You may need an excess of hydrazine to prevent the formation of dimers as the free NH2 in your product is still quite nucelophilic and the reaction would result in a build up of acid that would prevent your reaction from going to completion.

Thanks to all for your valuable inputs and resources.

I think you simply can try acetanilide and excess of hydrazine about 1.3 equivalent in ethanol and triethylamine (drops) as base. and reflux for suitable time. then evapourate the solvet to get your hydrazide product.

and I`m also agree with Brennan to chlorination at first with POCl3 then reaction with hydrazine hydrate.

You can try the both. but my experience recommend the first method.

Acetanilid is NOT a classical "ketone-type" carbonyl compound. At first ArN=C(CH3)OH presents, at second N-C bond is not so strong as C-C bond. So all your attemps to use the dirrect interacnion acetanilide with hydrazine lead to dectruction of target molecule  and formation of acetylhydrazine and free aniline. Other way - using imidioil chloride may be more sucsesful. But this reaction have to be  done in very mild conditions (very low temerature) in base solvent and without excess of hydrazine. The target compound may be unstable and (or) hydrolisable, espessially when heating. So, no distillation on purifing! And, may be,  chrmatography is not good metod too to purify such compound

Well explained by Dr. Petko

If you want to synthesize the target compound you follow the synthesis of chloro imine intermediate by PCl5 or POCl3

But still a question: Is this target compound stable enough to be isolated?

There is no possibility of a reaction between Acetanilide and hydrazine hydrate as amide carbonyl carbon  is less electrophilic. The addition is difficult.

Dear friend,

Kirill I. Petko say very well, carbon atom in this oxidation state undergors addition-elimination reacrion and you idea can be proceeds on this way. Your expected formula is well but can not udergoes addition but addition elimination reaction reaction.

Sorry.

P.