Synthesis and Applications in Catalysis of Metal Complexes with Chelating Phosphinosulfonate Ligands

Access to 3‐Oxindoles from Allylic Alcohols and Indoles

“…Interestingly, methods towards the introduction of an allylic or an alkyl fragment were developed by using transition‐metal‐catalyzed allylic substitution or borrowing hydrogen methodology and more recently by hydroelementation starting from simple allylic or aliphatic alcohols and alkynes or allenes; these methods provide a useful atom‐economical toolbox to access allylated and alkylated indoles. Recently, some of us reported the synthesis of an allylation ruthenium precatalyst by designing an allylic ruthenium(IV) complex featuring a phosphine–sulfonate chelate, and its efficiency in regio‐ and chemoselective allylation from various allylic alcohols was proven …”

“…According to previous independent reports of Kitamura, Pregosin, and us, an overall plausible mechanism for the allylation of indoles 1 is depicted in Figure . It involves activation of allylic alcohol 2 by the protonated sulfonate fragment of ruthenium(II) intermediate I ; this is followed by oxidative addition and release of a water molecule.…”

Lysosome‐targeted Cyclometalated Iridium (III) Anticancer Complexes Bearing Phosphine‐Sulfonate Ligands

“…The dinuclear Ir (III) precursors [Ir (ppy) 2 ] 2 Cl 2 (ppy = 2‐phenylpyridine) and the phosphine‐sulfonate ligands L1 ‐ L4 were prepared according to previous method . The complexes Ir1 ‐ Ir4 were obtained in moderate to high yield (48.4–69.2%) from the reaction of the appropriate [Ir (ppy) 2 ] 2 Cl 2 with the corresponding phosphine‐sulfonate ligand in CH 2 Cl 2 and CH 3 OH solution (Scheme ).…”

“…The dinuclear iridium (III) precursors [Ir (ppy) 2 ] 2 Cl 2 and phosphine‐sulfonate ligands were synthesized according to previous reported procedures All other reagents and solvents were obtained from commercial sources and used without further purification unless otherwise stated. 1 H NMR spectra were acquired at 298 K on Bruker DPX 500 (500 MHz).…”

Benzimidazolium sulfonate ligand precursors and application in ruthenium-catalyzed aromatic amine alkylation with alcohols

“…complexes have revealed good catalytic activity in the reaction of primary aliphatic amines with primary alcohols to form amides but no N-alkylation products were formed [28]. Based on the ability of the basic sulfonate group to transfer protons and generate water-soluble species [29], we decided to prepare new N-heterocyclic carbene sulfonate ligands constructed on the benzimidazole core, and evaluate their activity in the N-alkylation of aniline and 2-aminopyridine in the presence of ruthenium catalysts.…”