A New Synthesis Of 1,3,4-Oxadiazoles. Cyclization Of N.N'-Diacylhydrazeves Catalyzed By Palladium(0)

Synthesis of aromatic heterocycles

“…175 A more standard synthesis of 1,3,4-oxadiazoles is the cyclodehydration of 1,2-diacylhydrazines and this reaction has been carried out under palladium catalysis. 176 Palladium catalysis is also integral to another 1,3,4-oxadiazole synthesis: palladium catalysed carbonylation of aryl iodides followed by reaction with 5-phenyltetrazole gives 2-aroyl-5-phenyltetrazoles, from which 1,3-oxadiazoles are formed by thermal elimination of nitrogen. 177 A similar carbonylation procedure is involved in a one pot synthesis of 1,2,4-oxadiazoles (Scheme 51).…”

Diisopropylcarbodiimide: A Novel Reagent for the Synthesis of 1,3,4-Oxadiazoles on Solid-Phase

“…A number of recent publications on the synthesis of 1,2,4-5 , and 1,3,4oxadiazoles 6,7 in solution, employing novel cyclisation conditions to these systems, confirms the continuing interest in developing new methodology towards these important heterocycles. To date we have found only one reported synthesis of 1,3,4-oxadiazoles employing a solid-phase methodology 8 and the modest yields reported in this paper has prompted us to disclose our efforts in this area.…”

N,N′-Diacetyl-N′-[(4-nitrophenoxy)acetyl]acetohydrazide

“…For useful applications of hydrazide derivatives, see: Pang et al (2005); Lutun et al (1999); Liras et al (2000); Dhadialla et al (1998).…”

“…of insecticides (Dhadialla et al, 1998). Hydrazide derivates were also important intermediates in the synthesis of 1,3,4oxadiazole (Lutun et al, 1999;Liras et al, 2000), which was a significant heterocycle in chemical industy. In order to investigate its activity in anti-hyperglycaemia, we have synthesized the title compound.…”