Base Mediated Diazirination via Iodine(III) Reagents

Abstract

Herein, we described an efficient method for the construction of highly functionalized diazirines from the carbohydrazide and diazo-substituted hypervalent iodine reagents. Unambiguous transformation has been designed with user applicable and easy practicable conditions. Remarkably, D-glucose, menthol, aspirin, proline, and lithocholic acid were efficiently diazirinated. Furthermore, the method is mild, robust, and highly selective, which successfully converted a variety of aryl, alkyl, benzyl, and heterocyclic hydrazides into the corresponding diazirine derivatives.

α-Diazo-λ3-iodanes and α-diazo sulfonium salts: the umpolung of diazo compounds

“…The group of Singh described a novel route towards the synthesis of substituted diazirines 33 by reaction of semicarbazides 32 with 4, followed by oxidation of the diaziridine intermediate (Int-III) by air (Scheme 7b). 24 Also in the same year Rastogi and coworkers published a base assisted synthesis of [1,2,4]triazolo[4,3-a]pyridines 35, by reaction of 4 with pyridines and isoquinolines (Scheme 8). 25 Intermediates in this reaction are a-diazoalkyl pyridinium salts (Int-IV); compounds already described by Weiß in his seminal work.…”

Synthesis of Hypervalent Iodine Diazo Compounds and Their Application in Organic Synthesis

“…[68] In 2022, Singh et al described an efficient method for the synthesis of diazirines 49 using carbohydrazides 48 and compounds 3 as reaction substrates through the formation of C(sp 2 )À N bonds (Scheme 16). [69] The reaction process displayed that the S This synthesis method was mild, easy to operate, as well as highly selective, and successfully converted various aryl, alkyl, cycloalkyl, benzyl, and heterocyclic hydrazines 48 as well as compound 3 a into the corresponding diazirines derivatives in 66-80 % yields. In addition, the authors investigated the reactivity of different hypervalent iodine diazo reagents under standard conditions.…”

“…described an efficient method for the synthesis of diazirines 49 using carbohydrazides 48 and compounds 3 as reaction substrates through the formation of C(sp 2 )−N bonds (Scheme 16). [69] The reaction process displayed that the S N 2‐type nucleophilic reaction between carbohydrazide 48 and compound 3 generated intermediate A , accompanied by the elimination of TfOH and PhI. Then, intermediate A combined with proton to generate diazonium cation B , which underwent an intramolecular cyclization accompanied by denitrification to provide compound C .…”

Access to Functionalized Thiazolothiadiazoles via the Chemoselective Cascade Heteroannulation of Thioamides with Hypervalent Iodine Reagents

“…The β-ketothioamides possess multiple electrophilic and nucleophilic centers, which can preferably react with their choice of coupling partners in a chemo- or regioselective fashion to produce the corresponding heterocyclic compounds . Our research group is focused on developing a novel platform in organic synthesis using tailored hypervalent iodine reagents as an electrophilic diazo source. , To date, the reaction between β-ketothioamides and α-aryliodonio diazo compounds has not yet been accomplished and remains unexplored. As part of our continuing efforts on β-ketothioamides and α-aryliodonio diazo compounds, a new transition-metal- and base-free approach for the construction of thiazolothiadiazoles has been devised.…”

“…12 Our research group is focused on developing a novel platform in organic synthesis using tailored hypervalent iodine reagents as an electrophilic diazo source. 8,13 To date, the reaction between β-ketothioamides and αaryliodonio diazo compounds has not yet been accomplished and remains unexplored. As part of our continuing efforts on βketothioamides 14 and α-aryliodonio diazo compounds, a new transition-metal-and base-free approach for the construction of thiazolothiadiazoles has been devised.…”