The first one-pot ambient-temperature synthesis of 1,2,4-oxadiazoles from amidoximes and carboxylic acid esters

Baykov, Sergey V.; Sharonova, Tatyana; Shetnev, Аnton; Rozhkov, Sergey; Kalinin, Stanislav; Smirnov, Alexander

doi:10.1016/j.tet.2017.01.007

Cited by 69 publications

(43 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Due to their importance, several synthetic methods for preparing the 1,2,4‐oxadiazole ring systems have been reported . The general method for the preparation of 1,2,4‐oxadiazoles is the cyclization of O‐acylamidoximes obtained from acylation of amidoximes with acyl halides, esters or anhydrides . But preparation, isolation, and handling of them are difficult and they are commonly unstable.…”

Section: Introductionmentioning

confidence: 99%

A Mild and Efficient One‐Pot Preparation of 1,2,4‐Oxadiazoles from Nitriles and Carboxylic Acids Using Vilsmeier Reagent

Zarei

2018

ChemistrySelect

View full text Add to dashboard Cite

A one-pot synthesis of 1,2,4-oxadiazoles has been achieved from the corresponding amidoximes and carboxylic acids or from nitriles, hydroxylamine and carboxylic acids, employing the OH activation property of the Vilsmeier reagent. The precursor O-acylamidoxime could be derived in situ which underwent an intramolecular cyclization in the presence of Vilsmeier reagent to afford 1,2,4-oxadiazole. The products were simply obtained in good to excellent yields under mild condition and compatible with a range of functional groups. Utilization of easy workup and purification of products make it very interesting.

show abstract

Section: Introductionmentioning

confidence: 99%

A Mild and Efficient One‐Pot Preparation of 1,2,4‐Oxadiazoles from Nitriles and Carboxylic Acids Using Vilsmeier Reagent

Zarei

2018

ChemistrySelect

View full text Add to dashboard Cite

show abstract

“…Thus, the obtained result was astonishing and motivated us for the further investigation of this reaction directly in NaOH/DMSO medium. In previous work, we demonstrated that nucleophilicity of amidoximes drastically increases in DMSO, which explains the higher isolated yield of trans ‐diastereomer 3a compared to cis ‐diastereomer 3a′ (69 % and 34 % respectively, Scheme ).…”

Section: Resultsmentioning

confidence: 89%

Diastereoselective Opening of Bridged Anhydrides by Amidoximes Providing Access to 1,2,4‐Oxadiazole/Norborna(e)ne Hybrids

et al. 2019

Self Cite

View full text Add to dashboard Cite

A unique example of the one‐pot trans‐diastereoselective reaction of meso‐tricyclic anhydrides is reported. The process involves anhydride ring opening by an amidoxime and the sequential cis‐ to trans‐ epimerization/cyclodehydration of the O‐acylamidoxime intermediate. The resulted 1,2,4‐oxadiazole/norborna(e)ne hybrids are obtained in moderate to good yields and > 95 % diastereomeric excess without any additional purifications. These compounds are interesting not only for drug discovery but for other chemistry‐related fields due to the presence of two easily modifiable moieties.

show abstract

“…1,3-Dipolar cycloaddition of nitrile oxides with nitriles [14] and azetine [15] has been reported. The most popular strategy for the synthesis of 1,2,4-oxadiazoles is the O-acylation of amidoximes using activated carboxylic acid derivatives such as benzoyl cyanides, [16] esters, [17,18] anhydrides, [19,20] acid chlorides [21,22] and carboxylic acids, [23] followed by intramolecular cyclodehydration. Another method for the synthesis of 1,2,4-oxadiazole derivatives is the reaction of amidoxime with aldehydes for the synthesis of 4,5-dihydro-1,2,4-oxadiazoles, followed by oxidative dehydrogenation with chemical oxidants [24,25] or electrochemical oxidation methods.…”

Section: Introductionmentioning

confidence: 99%

Manganese oxide nanoparticles supported on graphene oxide as an efficient nanocatalyst for the synthesis of 1,2,4‐oxadiazoles from aldehydes

Saadati

Kaboudin

Hasanloei

et al. 2020

Applied Organom Chemis

View full text Add to dashboard Cite

The easy synthesis of graphene oxide (GO)‐supported manganese dioxide (MnO2) nanoparticles as a stable heterogeneous nanocatalyst (MnO2@GO) is described. This catalyst was investigated in the synthesis of 1,2,4‐oxadiazoles from amidoximes and aldehydes via a cyclization and oxidation process. The nanocomposite was prepared and characterized using various techniques. The catalytic application of the nanocomposite was examined in the reaction of a variety of aldehydes with aliphatic and aromatic amidoximes. The stable and robust catalyst was recycled for seven consecutive runs without a significant decrease in the catalytic activity.

show abstract

The first one-pot ambient-temperature synthesis of 1,2,4-oxadiazoles from amidoximes and carboxylic acid esters

Cited by 69 publications

References 38 publications

A Mild and Efficient One‐Pot Preparation of 1,2,4‐Oxadiazoles from Nitriles and Carboxylic Acids Using Vilsmeier Reagent

A Mild and Efficient One‐Pot Preparation of 1,2,4‐Oxadiazoles from Nitriles and Carboxylic Acids Using Vilsmeier Reagent

Diastereoselective Opening of Bridged Anhydrides by Amidoximes Providing Access to 1,2,4‐Oxadiazole/Norborna(e)ne Hybrids

Manganese oxide nanoparticles supported on graphene oxide as an efficient nanocatalyst for the synthesis of 1,2,4‐oxadiazoles from aldehydes

Contact Info

Product

Resources

About