New cyclopalladated benzothiophenes: a catalyst precursor for the Suzuki coupling of deactivated aryl chlorides

Abstract

Dimeric benzothiophene-based palladacycles were synthesized from thioanisole-substituted perfluoroalkyl propargyl imines and palladium(II) salts via an intramolecular thiopalladation pathway. The treatment of benzothiophene-based palladacycles with an excess of phosphine ligands in benzene at room temperature selectively afforded trans-bis(phosphine) palladium complexes in good yields. The trans-bis(tricyclohexylphosphine) palladium complex was found to be an active catalyst in the Suzuki coupling of electron rich aryl chlorides. The complex was also employed in the catalytic synthesis of sterically hindered biaryls. The anticancer activity of palladacycles is also discussed.

Anti-cancer palladium complexes: a focus on PdX2L2, palladacycles and related complexes

“…182 The phosphine based complexes were evaluated against DU145 human prostate carcinoma (HTB-81) cancer cells for anticancer activity. 183 The complexes initially were employed as catalysts for performing synthetically challenging cross-coupling processes and were later tested against three human leukemia cell lines, HL60 (human promyelocytic leukemia cells), K562 (chronic myelogenous leukemia) and CCRF-CEM (human acute lymphocytic leukemia). Complex 80e was found to be the most active followed by other complexes 80a-d (the bulkier the phosphine ligand the lower the activity recorded).…”

“…38). 183 The complexes initially were employed as catalysts for performing synthetically challenging cross-coupling processes and were later tested against three human leukemia cell lines, HL60 (human promyelocytic leukemia cells), K562 (chronic myelogenous leukemia) and CCRF-CEM (human acute lymphocytic leukemia). Complex 81a was found to exhibit the highest inhibition against all the three cancer cell lines, thus portraying excellent antitumour activity.…”

A palladium–phosphine catalytic system as an active and recycable precatalyst for Suzuki coupling in water

“…Recently, palladacycle complexes have been employed in Suzuki reactions, as active and more air-inert catalytic candidates [23][24][25][26]. In this context, we were interested to explore the use of a five-membered chelate ring palladacycle, whose X-ray crystal structure has been reported in our previous work [27], as a catalyst precursor for Suzuki cross-coupling in aqueous environments (Scheme 1).…”

A New Family of Doubly Cyclopalladated Diimines. A Remarkable Effect of the Linker between the Metalated Units on Their Cytotoxicity

“…Palladium complexes show a higher kinetic lability that can be modulated by means of the use of chelating ligands such as cyclometalated organic derivatives. Recently, a considerable number of palladacycles have been evaluated for cytotoxic activity against a variety of cancer cell lines with remarkable results …”