Synthesis of the 1,3,4‐Oxadiazole Core through Thermolysis of Geminal Diazides

Erhardt, Hellmuth; Mohr, Fabian; Kirsch, Stefan F.

doi:10.1002/ejoc.201601119

Cited by 24 publications

(22 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Herein, we report on the chemoselective reaction of tertiary azides with BCN ( 1 ) in the presence of sterically demanding ADIBO ( 2 ), which can thus selectively be reacted with primary or secondary azides. So far, only a few SPAAC reactions with secondary or even tertiary azides have been reported . We hypothesized that primary, secondary, and tertiary azides exhibit similar reactivity with sterically non‐demanding cyclooctynes, but expected a significant decrease in reactivity for tertiary azides when reacting with sterically demanding dibenzocyclooctynes (Figure b).…”

Section: Figurementioning

confidence: 97%

“…So far,o nly af ew SPAAC reactions with secondary or even tertiary azides have been reported. [31][32][33][34] We hypothesized that primary,s econdary,a nd tertiary azides exhibit similarr eactivity with sterically non-demanding cyclooctynes, but expected as ignificant decreasei nr eactivity for tertiary azides when reacting with sterically demanding dibenzocyclooctynes( Figure 1b).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Chemoselectivity of Tertiary Azides in Strain‐Promoted Alkyne‐Azide Cycloadditions

Svatunek

Houszka

Hamlin

et al. 2018

Chemistry A European J

View full text Add to dashboard Cite

The strain‐promoted alkyne‐azide cycloaddition (SPAAC) is the most commonly employed bioorthogonal reaction with applications in a broad range of fields. Over the years, several different cyclooctyne derivatives have been developed and investigated in regard to their reactivity in SPAAC reactions with azides. However, only a few studies examined the influence of structurally diverse azides on reaction kinetics. Herein, we report our investigations of the reactivity of primary, secondary, and tertiary azides with the cyclooctynes BCN and ADIBO applying experimental and computational methods. All azides show similar reaction rates with the sterically non‐demanding cyclooctyne BCN. However, due to the increased steric demand of the dibenzocyclooctyne ADIBO, the reactivity of tertiary azides drops by several orders of magnitude in comparison to primary and secondary azides. We show that this chemoselective behavior of tertiary azides can be exploited to achieve semiorthogonal dual‐labeling without the need for any catalyst using SPAAC exclusively.

show abstract

Section: Figurementioning

confidence: 97%

mentioning

confidence: 99%

Chemoselectivity of Tertiary Azides in Strain‐Promoted Alkyne‐Azide Cycloadditions

Svatunek

Houszka

Hamlin

et al. 2018

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…In ar ecent report on the thermolysis of geminal diazides derived from acylacetate compounds, we found that the migration of the carbonylg roups is favored over the migration of esters and amides;i n this particular case, however,t he initially formed tetrazole intermediate undergoes af urther Huisgen rearrangement [30] that resultsi nt he construction of the 1,3,4-oxadiazole core. [31] Future studies will test the migration tendencies of other groups, with the goal to fully understand the synthetic potential of thermolysis reactions with geminal diazides.…”

Section: Resultsmentioning

confidence: 99%

A Synthetic Route Toward Tetrazoles: The Thermolysis of Geminal Diazides

Holzschneider

Tong

Mohr

et al. 2019

Chemistry A European J

Self Cite

View full text Add to dashboard Cite

A new synthetic route toward the tetrazole core is described, which is based on a general fragmentation pattern that was found in a range of compounds featuring geminal diazido units. Through a simple two‐step procedure, the synthesis of structurally diverse target compounds containing a tetrazole, such as tetrazoloquinoxalinones, benzoylaryltetrazoles, tetrazolotriazinones, and tetrazoloazepinones, was easily accomplished, starting from broadly accessible substrates (i.e., oxindoles, diarylethanones, pyrazolones, and phenanthrols). The initial oxidative diazidation reaction with iodine and sodium azide under mild conditions is followed by the thermal fragmentation under microwave irradiation, leading to the tetrazole products. Noteworthy, an experimental solution is presented in which the potentially hazardous diazide intermediates are not isolated and the concentration of crude reaction mixtures containing diazides is not required to achieve the tetrazoles in good yields.

show abstract

“…Although the reaction was only tested with two substrates, leading to 26a and 26b (Scheme 8A), we showed decades later that this reaction is of general appeal, allowing for the oxadiazole synthesis with a reasonably broad scope (Scheme 8B). [ 44 ]…”

Section: Reactivities Of Geminal Diazidesmentioning

confidence: 99%

Reactivity of Organic Geminal Diazides at Tetrahedral Carbons

Çelik

Kirsch

2020

Eur J Org Chem

Self Cite

View full text Add to dashboard Cite

Organic compounds with geminal diazide units at sp3‐hybridized carbon atoms are a widely neglected class of compounds, with regard to their synthesis and their reactivities. In the last decade, we and others started to uncover reactivity patterns with this compound class, leading to new possibilities of reaction design. This minireview covers recent developments in the field, including the generation of heterocycles through thermolysis, the reactions with nucleophilic amines, and the hydrogenation.

show abstract

Synthesis of the 1,3,4‐Oxadiazole Core through Thermolysis of Geminal Diazides

Cited by 24 publications

References 62 publications

Chemoselectivity of Tertiary Azides in Strain‐Promoted Alkyne‐Azide Cycloadditions

Chemoselectivity of Tertiary Azides in Strain‐Promoted Alkyne‐Azide Cycloadditions

A Synthetic Route Toward Tetrazoles: The Thermolysis of Geminal Diazides

Reactivity of Organic Geminal Diazides at Tetrahedral Carbons

Contact Info

Product

Resources

About