One-pot PEG-mediated syntheses of 2-(2-hydrazinyl) thiazole derivatives: novel route

Synthetic Strategies for Hydrazinyl Thiazole Derivatives

“…Here we have shown different reaction strategies developed by different research groups for the synthesis of hydrazinyl thiazoles. Some of them are catalyst-free, [38,39] some are both catalyst and solvent-free, [40,41] while some are catalyzed by homogeneous, [17,[42][43][44][45][46][47][48][49][50] and heterogeneous [51][52][53][54] catalysts. All the processes have some advantages over each other and also have some limitations.…”

“…In 2017 Raut et al . reported [43] a novel route for the one‐pot synthesis of hydrazinyl thiazoles mediated by PEG‐300. Here they prepared it using substituted acetophenones 30 , thiosemicarbazide 10 , and substituted phenacyl bromides 31 in presence of PEG‐300 at 70–75 °C in 2 h (Scheme 8).…”

An Overview of Recent Developments in the Synthesis of Substituted Thiazoles

“…Raut and coworkers developed a single step method for preparing of 2‐(2‐hydrazinyl) thiazole derivatives ( 212 ) in PEG‐300 (Polyethylene glycol 300) as media from ketones ( 160 ), thiosemicarbazide ( 178 ), and α ‐halo ketones ( 211 ). This reaction proceeded well without any rearranged products (Scheme ).…”

An Efficient Method for the One‐pot Synthesis of 4‐Phenyl‐hydrazinyl Thiazole Derivatives Using Nano‐SiO2

“…Also, various thiazoles such as 2‐arylthiazole received much attention due to unique structure and its usage as anticancer agents . There are some methods for the synthesis of hydrazinyl‐thiazole derivatives such as reaction of 4‐(4‐nitrophenoxy)phenyl thiourea with substituted phenacyl bromide ; condensation of cyclic ketones or arylaldehydes with thiosemicarbazide and then reaction of the obtained thiosemicarbazones with α‐haloketones ; reaction of 3‐pyridinecarboxaldehyde or 2/3/4‐acetylpyridine with thiosemicarbazide in 2–4 drops of glacial acetic acid in ethanol and then condensation of obtained thiosemicarbazones with phenacyl bromides in the presence of triethylamine ; PEG‐300‐mediated synthesis of 2‐(2‐hydrazinyl)thiazole derivatives from ketones, thiosemicarbazide, and phenacyl bromides ; reaction of pyrazolecarbaldehydes, thiosemicarbazide, acetophenones, and N ‐bromosuccinimide using KIT‐6 mesoporous silica‐coated magnetite nanoparticles ; CuO NPs/TiO 2 catalyzed synthesis of hydrazinyl‐thiazoles via reaction of aldehydes/ketones with thiosemicarbazide and phenacyl bromide derivatives and by reaction of pyrazolecarbaldehyde derivatives with thiosemicarbazide and bromoacetophenones in the presence of [PDBMDIm] Br . Due to the significance of thiazole derivatives from a pharmaceutical and biological standpoint, there is still a requirement to extend effective, one step, and affordable procedures for the synthesis of 4‐phenyl‐hydrazineyl thiazoles.…”