19226-10-9

Upstream product

• 106538-30-1 N'-ethoxycarbonyl-N'-phenylbenzohydrazide 
• 100-63-0 phenylhydrazine 
• 532-96-7 N-benzoyl-N'-phenylhydrazine 
• 201230-82-2 carbon monoxide 
• 508191-77-3 3-phenylsydnone 
• 13183-09-0 3-phenyl-4-bromosydnone 
• 124-38-9 carbon dioxide 
• 100-52-7 benzaldehyde 
• 588-64-7 benzaldehyde phenylhydrazone 
• 1199-02-6 5-phenyl-3H-[1,3,4]oxadiazol-2-one 
• 66003-76-7 Diphenyliodonium triflate 
• 613-94-5 benzoic acid hydrazide 
• 591-50-4 iodobenzene 
• 98-88-4 benzoyl chloride 

Downstream Products

• 34241-53-7 3,3',5,5'-tetraphenyl-2(3H),2'(3'H)-spirobi-1,3,4-thiadiazole 
• 93326-84-2 2,5-diphenyl-3,4-dihydro-2H-pyrazole-3r,4c-dicarboxylic acid anhydride 

Relevant academic research and scientific papers

Copper-Catalyzed Selective N-Arylation of Oxadiazolones by Diaryliodonium Salts

Here, we report the method for copper-catalyzed N-arylation of diverse oxadiazolones by diaryliodonium salts under mild conditions in high yields (up to 92%) using available CuI as a catalyst. The developed method allows utilizing both symmetric and unsymmetric diaryliodonium salts bearing auxiliary groups such as 2,4,6-trimethoxyphenyl (TMP). We found that the steric effects in aryl moieties determined the chemoselectivity of N- and O-arylation of the 1,2,4-oxadiazol-5(4H)-ones. Mesityl-substituted diaryliodonium salts demonstrated the high potential as a selective arylation reagent. The structural study suggests that steric accessibility of N-atom in 1,2,4-oxadiazol-5(4H)-ones impact to arylation with sterically hindered diaryliodonium salts. The synthetic application of proposed method was also demonstrated on selective arylation of 1,3,4-oxadiazol-2(3H)-ones and 1,2,4-oxadiazole-5-thiol. (Figure presented.).

One-pot synthesis of 1,3,4-oxadiazol-2(3H)-ones with CO2 as a C1 synthon promoted by hypoiodite

A convenient and efficient route has been developed to synthesize 1,3,4-oxadiazol-2(3H)-ones from CO2, hydrazines and aryl or aliphatic aldehydes. Promoted by hypoiodite (IO-) generated in situ from KI and oxidant TBHP, the one-pot synthesis could proceed smoothly to afford the desired products in moderate to high yields. Mechanism studies revealed that nitrile imine was an important intermediate in this transformation. Notably, a commercial herbicide Oxadiazon could be successfully synthesized by this route.

The reaction of sydnones with bromine in acetic anhydride revisited: A new route to 5-substituted-3-aryl-1,3,4-oxadiazol-2(3H)-ones from N-aryl-N-bromocarbonylhydrazines

The reaction of 3-phenylsydnone with bromine in acetic anhydride to form 5-methyl-3-phenyl-1,3,4-oxadiazol-2(3H)-one has been reexamined and improved. A new mechanism involving a bromocarbonylhydrazine species is proposed and its intermediacy is supported

1,3-Dipolar Cycloaddition of Nitrile Imine with Carbon Dioxide: Access to 1,3,4-Oxadiazole-2(3H)-ones

Efficient synthesis of 1,3,4-oxadiazole-2(3H)-one was achieved by CsF/18-crown-6 mediated 1,3-dipolar cycloaddition of nitrile imine and 2.0 MPa of CO2. CsF/18-crown-6 played a key role in enhancing the reactivity of CO2 as a 1,3-dipolarophile. The practical utility of this transition-metal-free approach to 1,3,4-oxadiazole-2(3H)-one is highlighted by the convenient synthesis of a commercial herbicide Oxadiazon and a MAO B inhibitor.

Method for synthesizing 1,3,4-oxadiazole-2-one compounds of oxadiazon and the like by carbon dioxide

The invention discloses a method for synthesizing 1,3,4-oxadiazole-2-one compounds of oxadiazon and the like by carbon dioxide. The method comprises: adding an acyl halide hydrazone raw material and a solvent into a high-pressure autoclave; using alkali and an additive as accelerants, introducing carbon dioxide, and performing a stirring reaction for 6 to 24 hours at a temperature of 0 to 70 DEG C; after finishing the reaction, cooling to the room temperature; slowly releasing the unreacted carbon dioxide; after adding water to dilute reaction liquid, carrying out extraction by ethyl acetate; concentrating to obtain a crude product; purifying by column chromatography to obtain the 1,3,4-oxadiazole-2-one compounds. The method disclosed by the invention uses the carbon dioxide for replacing conventional phosgene and carbon monoxide, is safe and simple to operate, low in toxicity, friendly to the environment, simple and easy for obtaining reaction raw materials and reagents, wide in universality of a type of a reaction substrate, simple in post-processing process, high in target product yield and beneficial to industrial production, and is widely applied in synthesis of pesticides, medicines and natural products.

Palladium-catalyzed oxidative carbonylation of hydrazides: Synthesis of 1,3,4-oxadiazol-2(3H)-ones

A novel palladium-catalyzed oxidative carbonylation reaction was developed via the carbon monoxide insertions between the amine group and the carbonyl group to realize the intramolecular cyclization, which provides efficient access to 1,3,4-oxadiazol-2(3H)-ones with a wide range of substrates under mild conditions, resulting in good to excellent yields.

Palladium-catalyzed oxidative O-H/N-H carbonylation of hydrazides: Access to substituted 1,3,4-oxadiazole-2(3 H)-ones

A novel palladium-catalyzed oxidative annulation reaction for the C-O, C-N bond formations is developed. The intramolecular cyclocarbonylation provides an efficient and direct approach for the construction of valuable 1,3,4-oxadiazole-2(3H)-ones and their

New General Synthesis of Tetrahydro-1,2,4,5-tetrazin-3(2H)-one Derivatives and Stable 3,4-Dihydro-3-oxo-1,2,4,5-tetrazin-1(2H)-yl Radical Derivatives

Reactions of 2-chloroformylhydrazones of aromatic aldehydes or ketones 2 with various hydrazines were converted to monocarbonohydrazone derivatives 3 or 5 and/or tetrahydro-1,2,4,5-tetrazin-3(2H)-one derivatives 6,7.By oxidation with lead dioxide, compounds 6 were transformed into stable 3,4-dihydro-3-oxo-1,2,4,5-tetrazin-1(2H)-yl radical derivatives 8.

Benzohydrazides, Benzothiohydrazides, and Benzamidrazones as Sources of 1,3,4(2H)-Oxadiazolenones, 1,3,4(2H)-Thiadiazolenones, and 1,2,4(5H)-Triazolenones

Benzohydrazides, benzothiohydrazides, and benzamidrazones have been converted to 1,3,4(2H)-oxadiazolenones, 1,3,4(2H)-thiadiazolenones, and 1,2,4(5H)-triazolenones respectively by reaction with ethyl chloroformate, with ethyl thiolchlorformate, and with phenyl isocyanate.In some reactions, a carbamate or urea has been isolated as intermediate.