215545-72-5

Upstream product

• 15646-46-5 4-ethoxymethylene-2-phenyl-2-oxazolin-5-one 
• 613-94-5 benzoic acid hydrazide 

Downstream Products

• 93-98-1 N-phenyl benzoyl amide 
• 109702-97-8 N-(3-oxo-2,3-dihydro-1H-pyrazol-4-yl)-benzamide 
• 582-78-5 N-(4-methylphenyl)benzamide 
• 7190-96-7 N'-(6-chloropyridazin-3-yl)benzohydrazide 
• 7190-80-9 6-Chloro-3-phenyl-s-triazolo<4,3-b>pyridazine 
• 142346-13-2 6-chloro-8-methyl-3-phenyl-1,2,4-triazolo[4,3-b]pyridazine 

Relevant academic research and scientific papers

4-Acylhydrazinomethylene-2-phenyloxazol-5(4H)-ones as acylating agents: Synthesis of salicylanilides and 1,2,4-triazolo[4,3-b] pyridazines

A simple and general method for the acylation of an amino or hydrazino group by the application of hydrazides has been developed. It starts from hydrazides (2), which are converted with 4-ethoxymethylene-2-phenyl-oxazol-5(4H)-one (1) to the corresponding 4-acylhydrazinomethylene-2-phenyloxazol-5(4H)-ones (3). The latter react with nitrogen-containing nucleophiles in 1,4-dioxane in the presence of triethylamine or zirconium(IV) chloride to give the corresponding amides (7) or mixtures of hydrazides (12) and 1,2,4-triazolo[4,3-b]pyridazines (11). Upon prolonged heating, compounds (11) are the main products.

Migration of an acyl group in the pyrazole system: Synthesis of 1-acyl-3-hydroxy-1H-pyrazoles and related derivatives. A new preparation of N,N′-diacylhydrazines

A new general method for the synthesis of 1-acyl-3-hydroxy-1H-pyrazoles 5a-f and related derivatives 5g-i starting from 4-ethoxymethylene-2-phenyloxazol-5(4H)-one (1) and hydrazides, 4-phenylsemicarbazide, 4-phenylthiosemicarbazide and benzyl carbazate in boiling dioxane is described. The method includes a migration of an acyl or related unit. The X-ray study and NMR spectroscopic examination confirmed the structure of the products. A one-pot synthesis of N,N′-diacylhydrazines from hydrazides by the assistance of oxazolone 1 is also presented.