92437-24-6

Upstream product

• 18489-25-3 5-benzyl-1H-tetrazole 
• 93-97-0 benzoic acid anhydride 
• 103-82-2 phenylacetic acid 
• 613-94-5 benzoic acid hydrazide 
• 100-52-7 benzaldehyde 
• 937-39-3 2-phenylacetylhydrazine 
• 103-80-0 phenylacetyl chloride 
• 109435-47-4 2-phenylethylidenebenzohydrazide 
• 122-78-1 phenylacetaldehyde 
• 591-50-4 iodobenzene 
• 119072-55-8 tert-butylisonitrile 
• 18039-42-4 5-Phenyl-1H-tetrazole 
• 6125-24-2 2-Phenylnitroethane 
• 101-41-7 benzeneacetic acid methyl ester 

Downstream Products

• 130781-64-5 3-Benzyl-4-butyl-5-phenyl-4H-[1,2,4]triazole 
• 130781-65-6 3,4-Dibenzyl-5-phenyl-4H-[1,2,4]triazole 

Relevant academic research and scientific papers

Synthesis of 1,3,4-oxadiazoles from 1,2-diacylhydrazines using [Et 2NSF2]BF4 as a practical cyclodehydration agent

The preparation of 1,3,4-oxadiazoles from 1,2-diacylhydrazines using XtalFluor-E ([Et2NSF2]BF4) as cyclodehydration reagent is described. Various functionalized 1,3,4-oxadiazoles were synthesized and it was found that the use of acetic acid as an additive generally improved the yields.

The preparation, characterization and catalytic activity of Ni NPs supported on porous alginate-g-poly(p-styrene sulfonamide-co-acrylamide)

Herein, we report the synthesis of nickel nanoparticles under mild conditions using porous alginate-g-poly(p-styrene sulfonamide-co-acrylamide) as a protecting/stabilizing agent and sodium borohydride as a reducing agent. The porous cross-linked polymeric support was preparedviacombining the use of sol-gel, nanocasting, and crosslinking techniques, in which thep-styrene sulfonamide monomer (PSSA) andN,N′-methylene-bis (acrylamide) (MBA) cross-linker underwent copolymerization on the surface of sodium alginate in the presence of a SiO2nanoparticle (NP) template (Alg-PSSA-co-ACA). The prepared catalyst (Alg-PSSA-co-ACA@Ni) showed high catalytic activity for the one-step synthesis of 1,3,4-oxadiazoles from the reaction of hydrazides and aryl iodides through isocyanide insertion/cyclization.

UV-Induced 1,3,4-Oxadiazole Formation from 5-Substituted Tetrazoles and Carboxylic Acids in Flow

A range of 1,3,4-oxadiazoles have been synthesized using a UV-B activated flow approach starting from carboxylic acids and 5-substituted tetrazoles. The application of UV light represents an attractive alternative to the traditional thermolytic approach and has demonstrated comparable efficiency and versatility, with a diverse substrate scope, including the incorporation of highly substituted amino acids.

Electrophilic activation of nitroalkanes in efficient synthesis of 1,3,4-oxadiazoles

A novel methodology for general and chemoselective preparation of non-symmetric 1,3,4-oxadiazoles is developed. This unusual reaction proceeds via polyphosphoric acid-assisted activation of nitroalkanes towards nucleophilic attack with acylhydrazides.

Study on DDQ-promoted synthesis of 2, 5-disubstituted 1, 3, 4-oxadiazoles from acid hydrazides and aldehydes

A facile stepwise synthesis of 2, 5-disubstituted 1, 3, 4-oxadiazoles proceeding via oxidative cyclization of N-acylhydrazones is reported. The reaction is efficiently promoted by 2, 3-dichloro-5, 6-dicyano-1, 4- benzoquinone (DDQ) to afford the desired products mostly in high yields and in relatively short times. The final 1, 3, 4-oxadiazole derivatives are also synthesized directly from acid hydrazides and aldehydes in a one-pot procedure. The substrate scope and limitations of the reported transformation are discussed in detail.

One-pot cyclization/decarboxylation of α-keto acids and acylhydrazines for the synthesis of 2,5-disubstituted 1,3,4-oxadiazoles under transition-metal-free conditions

A one-pot KI/TBHP-mediated oxidative cyclization of α-keto acids with acylhydrazines was developed. A series of functional 2,5-disubstituted 1,3,4-oxadiazoles were synthesized through a tandem keto amine condensation followed by oxidative cyclization and decarboxylation reactions. This procedure was achieved under transition-metal-free conditions and showed advantages including readily available materials, mild reaction conditions and good group tolerance.

Efficient oxidative cyclization of N -acylhydrazones for the synthesis of 2,5-disubstituted 1,3,4-oxadiazoles using t-BuOI under neutral conditions

An efficient procedure for the oxidative cyclization of N -acylhydrazones was developed utilizing tert-butyl hypoiodite (t-BuOI), which is generated in situ from t -BuOCl and NaI. A variety of 2,5-disubstituted 1,3,4-oxadiazoles were synthesized in high yields within short reaction time. The method is also suitable for cyclization of N -acylhydrazones derived from heterocyclic aldehydes and aliphatic aldehydes. Mild reaction conditions and simple workup operations make the procedure a good alternative for the synthesis of 2,5-disubstituted 1,3,4-oxadiazoles.

Efficient oxidative cyclisation of acid hydrazides to 2,5-disubstituted 1,3,4-oxadiazoles catalysed by Bu4NI with t-BuOOH as oxidant

Acid hydrazides or araldehyde N-acylhydrazones can be converted in good yields to, respectively, symmetrical or unsymmetrical, 2,5-disubstituted 1,3,4-oxadiazoles at 60 °C by a Bu4NI-catalysed procedure which requires the presence of a base and 2.5 equiv. of t-butyl hydroperoxide.

Oxadiazoles in medicinal chemistry

Oxadiazoles are five-membered heteroaromatic rings containing two carbons, two nitrogens, and one oxygen atom, and they exist in different regioisomeric forms. Oxadiazoles are frequently occurring motifs in druglike molecules, and they are often used with the intention of being bioisosteric replacements for ester and amide functionalities. The current study presents a systematic comparison of 1,2,4- and 1,3,4-oxadiazole matched pairs in the AstraZeneca compound collection. In virtually all cases, the 1,3,4-oxadiazole isomer shows an order of magnitude lower lipophilicity (log D), as compared to its isomeric partner. Significant differences are also observed with respect to metabolic stability, hERG inhibition, and aqueous solubil ity, favoring the 1,3,4-oxadiazole isomers. The difference in profile between the 1,2,4 and 1,3,4 regioisomers can be rationalized by their intrinsically different charge distributions (e.g., dipole moments). To facilitate the use of these heteroaromatic rings, novel synthetic routes for ready access of a broad spectrum of 1,3,4-oxadiazoles, under mild conditions, are described.

Reactions of α-mercaptocarboxylic acid hydrazides with triethyl orthoesters: Synthesis of 1,3,4-thiadiazin-5(6H)-ones and 1,3,4-oxadiazoles

Reactions of α-mercapto-β-phenylpropionic and α-mercaptophenylacetic acid hydrazides with triethyl orthoesters were conducted under N2 in glacial acetic acid and resulted in the formation of two groups of products, derivatives of 1,3,4-thiadiazin-5(6H)-ones and 2-(1-mercaptomethyl)-1,3,4-oxadiazoles. When conducting the same transformations on α-mercaptophenylacetic acid hydrazide in the presence of air, two different products from the 1,3,4-oxadiazole family, the appropriate bis(1,3,4-oxadiazol-2-yl-phenylmethyl) disulfides and 2-benzyl-1,3,4- oxadiazoles, were formed with the liberation of free sulfur. The oxygenated bis(1,3,4-oxadiazol-2-yl-phenylmethyl) disulfides were reduced to the corresponding 2-(1-mercaptomethyl)-1,3,4-oxadiazoles with the use of zinc powder under mild conditions.