Michael Addition with an Olefinic Pyridine: Organometallic Nucleophiles and Carbon Electrophiles

Abstract

The conjugate addition reactions of trans-1,2-di-(2-pyridyl)ethylene have been studied. This substrate reacts with organolithium nucleophiles and the resulting anionic intermediates may be trapped by proton or various carbonyl-based electrophiles. It is suggested that the dipyridyl structure stabilizes the intermediate carbanion, allowing the Michael adduct to be captured by an added electrophile.

A predictive chemistry DFT study of N2O functionalization for the preparation of triazolopyridine and triazoloquinoline scaffolds

“…Species A can then be trapped by nitrous oxide acting as an electrophile, as described by Stenzel and Klumpp in 2020. 75 The rds corresponds to the hydrogen transfer from the former carbanion to the oxygen of nitrous oxide, the activation energy being 35.2 kcal mol −1 , thus justifying the low experimental yield obtained.…”

Progress on Pyridotriazole Chemistry: Synthesis and Transformations

“…However, the reactions of pyridines bearing simple alkyl substituents at C(2) position gave complex mixture, indicating the limitation of the method. Following Klumpp's procedure for generating 2‐alkylpyridine anions from the reaction of 2‐alkenyl pyridines with organolithium reagents, [36] the method was further extended to the synthesis of 3‐α‐tertiary pyridotriazoles 17 in moderate yields via a one‐pot three‐component reaction of 2‐alkenyl pyridines 15 , alkyllithium reagents 16 and nitrous oxide (Scheme 8).…”

A novel fluorescent probe for rapid detection of sulfur dioxide in living cells

“…Compared to these classical detection methods, fluorescence imaging technology has superiority in biological researches which could serve as a powerful tool for real-time detection of ions and biomolecules in living organisms. [24] It is known that many delocalized lipophilic cationic dyes, [25][26][27][28] which have a complete positive charge are easily accumulated and absorbed by living cells. [29] Recently, although many SO 2 Abbreviations used: Cys, cysteine; DMEM, Dulbecco's modified Eagle's medium; DMSO, dimethylsulfoxide; ESI, electrospray ionization; HPLC, high-performance liquid chromatography; HR-MS, high resolution mass spectrascopy; FIA, flow injection analysis; NMR, nuclear magnetic resonance; PBS, phosphate-buffered saline; SD, standard deviation; SO 2 , sulfur dioxide; TBHP, tert-Butyl hydroperoxide; TLC, thin layer chromatography; UV, ultraviolet.…”