Modular Synthesis of N-Vinyl Benzotriazoles

Abstract

A modular approach to N1-vinyl benzotriazoles by azide–aryne cycloadditions and Julia–Kocienski reactions is described. Reactions of azidomethyl phenyl-1H-tetrazol-5-yl (PT) sulfide with arynes gave methyl(PT-sulfanyl)-substituted benzotriazoles in 68–89% yields. Oxidation of the sulfides to the sulfones gave the benzotriazole-substituted Julia–Kocienski reagents. Olefination reactions of aldehydes and a ketone with reagents derived from benzyne, 2,3-naphthyne, and 4,5-dimethoxybenzyne precursors proceeded to give various N1-vinyl benzotriazole derivatives. Olefination stereoselectivities are tunable for electron-rich aldehydes, but not for electron-deficient aldehydes and alkanals, where they proceed with good to excellent Z-stereoselectivity.

l‐Proline: an efficient N,O‐bidentate ligand for copper‐catalyzed intramolecular cyclization reaction of 2‐iodoanilines with nitriles for the synthesis of benzimidazoles

“…They exhibit significant pharmacological and biological activities such as anticonvulsant, anticancer, antiulcer, antihypertensive, antibacterial and antihistaminic properties. [1][2][3][4][5] In addition, they have been applied in other fields, such as chemosensing, [6] dyes, [7] fluorescence and corrosion science. [8] Their synthesis is one of the most exciting topics in practical organic synthesis.…”

Highly Efficient Synthesis of 1‐Nitroindolizine Derivatives via the DBU/Acetic Acid System

“…Herein, we disclose practical and convenient procedures to synthesize various derivatized 1-nitroindolizines with pyridinium ylides and nitroalkenes in presence of DBU/AcOH system ( Figure 2). [21]…”

Transition-Metal-Free Synthesis of Benzo-Fused Five- and Six-Membered Heterocycles Employing Arynes

“…The scope of this click reaction was broad tolerating a variety of functional groups. Recently, Zajc and coworkers demonstrated the synthesis of N-vinyl benzotriazoles by azide-aryne cycloadditions followed by an oxidation/Julia-Kocienski reaction sequence [36]. The azide-aryne 1,3-dipolar cycloaddition reaction using in situ-generated azides resulting in an efficient synthesis of substituted benzotriazoles was developed by Zhang and Moses (Scheme 12) [35].…”

“…Additionally, they applied this methodology to the synthesis of oxa[3.2.1]octane core of SCHEME 11 Aryne click reaction: reaction of an azide with aryne [34]. SCHEME 13 Synthesis of N-vinyl benzotriazoles [36]. SCHEME 13 Synthesis of N-vinyl benzotriazoles [36].…”