Domino Construction of Benzoxazole-Derived Sulfonamides via Metal-Free Denitrogenation of 5-Iodo-1,2,3-triazoles in the Presence of SO₂ and Amines

Abstract

A straightforward domino approach to assemble benzoxazole-derived sulfonamides has been developed. The method is based on annulation-induced in situ generation of diazo compounds from readily available 2-(5-iodo-1,2,3-triazolyl)phenols, followed by metal-free denitrogenative transformation upon the action of 1,4-diazabicyclo[2.2.2]octane bis(sulfur dioxide) (DABSO) and amines. The protocol is operationally simple and features a broad substrate scope, furnishing a library of target compounds in generally good yields.

Synthesis of Bench‐stable Polycyclic Organophosphorus Heterocycles via Staudinger‐type Annulations of ortho‐Azidophenols

“…The authors have cited additional references within the Supporting Information. [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]…”

Regioselective Synthesis of NO-Donor (4-Nitro-1,2,3-triazolyl)furoxans via Eliminative Azide–Olefin Cycloaddition

“…In a series of nitrogen heterocycles, 1,2,3-triazoles have become of paramount importance over the past two decades due to their universal application in diverse fields, such as drug development and medicinal chemistry [37][38][39], materials science and polymers [40,41]. In addition, they contribute to organic synthesis by acting as synthetic precursors to many valuable compounds [42][43][44]. In this regard, nitro-1,2,3-triazoles acquire additional significance due to their potential application in energetic materials science and for medicinal chemistry needs [45][46][47].…”

Annulation-Triggered Denitrogenative Transformations of 2-(5-Iodo-1,2,3-triazolyl)benzoic Acids

“…Recently, we have developed a new approach to heterocycle-fused triazoles via intramolecular nucleophilic substitution in 5-iodo-1,2,3-triazoles (Scheme B). This approach, along with stable triazoles, allows access to diazobenzoxazoles . Herein, we present the application of this method to produce triazole-fused lactones, which can serve as versatile diazo precursors via divergent reaction pathways (Scheme C).…”