225931-80-6Relevant articles and documents
Water-Soluble Palladium Reagents for Cysteine S-Arylation under Ambient Aqueous Conditions
Rojas, Anthony J.,Pentelute, Bradley L.,Buchwald, Stephen L.
, p. 4263 - 4266 (2017)
We report the use of a sulfonated biarylphosphine ligand (sSPhos) to promote the chemoselective modification of cysteine containing proteins and peptides with palladium reagents in aqueous medium. The use of sSPhos allowed for the isolation of several air-stable and water-soluble mono- and bis-palladium reagents, which were used in an improved protocol for the rapid S-arylation of cysteines under benign and physiologically relevant conditions. The cosolvent-free aqueous conditions were applied to the conjugation of a variety of biomolecules with affinity tags, heterocycles, fluorophores, and functional handles. Additionally, bis-palladium reagents were used to perform macrocyclization of peptides bearing two cysteine residues.
A Neophyl Palladacycle as an Air- And Thermally Stable Precursor to Oxidative Addition Complexes
Buchwald, Stephen L.,King, Ryan P.,Krska, Shane W.
supporting information, p. 7927 - 7932 (2021/10/25)
The utilization of isolated Palladium Oxidative Addition Complexes (OACs) has had a significant impact on Pd-catalyzed and Pd-mediated cross-coupling reactions. Despite their importance, widespread utility of OACs has been limited by the instability of their precursor complexes. Herein, we report the use of Cámpora's palladacycle as a new, more stable precursor to Pd OACs. Using this palladacycle, a series of biarylphosphine ligated OACs, including those with pharmaceutical-derived aryl halides and relevance to bioconjugation, were prepared.
Carboxylation of Aryl Triflates with CO2 Merging Palladium and Visible-Light-Photoredox Catalysts
Bhunia, Samir Kumar,Das, Pritha,Nandi, Shantanu,Jana, Ranjan
supporting information, p. 4632 - 4637 (2019/06/27)
We report herein a visible-light-promoted, highly practical carboxylation of readily accessible aryl triflates at ambient temperature and a balloon pressure of CO2 by the combined use of palladium and photoredox Ir(III) catalysts. Strikingly, the stoichiometric metallic reductant is replaced by a nonmetallic amine reductant providing an environmentally benign carboxylation process. In addition, one-pot synthesis of a carboxylic acid directly from phenol and modification of estrone and concise synthesis of pharmaceutical drugs adapalene and bexarotene have been accomplished via late-stage carboxylation reaction. Furthermore, a parallel decarboxylation-carboxylation reaction has been demonstrated in an H-type closed vessel that is an interesting concept for the strategic sector. Spectroscopic and spectroelectrochemical studies indicated electron transfer from the Ir(III)/DIPEA combination to generate aryl carboxylate and Pd(0) for catalytic turnover.
