A method for the synthesis of bulky 2-anilinotropones has been developed, utilizing palladium-catalyzed cross-coupling techniques. Deprotonation of these anilinotropones followed by reaction with (PPh3)2Ni(Ph)Cl produces ethylene polymerization catalysts of the general formula [[(2-R-6-R‘C6H3)NC7H5O]Ni(Ph)(PPh3)] (3a−j:  R, R‘ = Me, Me (a), iPr, iPr (b), tBu, H (c), tBu, Me (d), Ph, Ph (e), Cl, Cl (f), Br, Br (g), 2,3,4,5,6-F5 (h), Me, H (j), Me, CF3 (k)). Ethylene polymerizations with 3a−j have been explored under a variety of reaction conditions. The complex [[(2,6-iPr2C6H3)NC7H4O(7-aryl)]Ni(Ph)(PPh3)] (14:  aryl = phenyl (a), 1-naphthyl (b)), possessing steric bulk at the 7-position, have been prepared and are both long-lived and active ethylene polymerization catalysts. At low temperatures 14a,b produce polyethylene with narrow molecular weight distributions (MWD ca. 1.2). The polymerization results suggest that chain transfer occurs via a β-hydride elimination pathway and that catalyst decomposition proceeds through reductive elimination of the free ligand from a nickel−hydride intermediate.

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A Pauson−Khand type conversion of enynes to bicyclic cyclopentenones employing the commercially available precatalyst titanocene dicarbonyl is described. This methodology shows excellent functional group tolerance for a group 4 metallocene-catalyzed process. The scope and limitations of this cyclization with respect to 1,6-, 1,7- and 1,8-enynes with a variety of terminal alkyne substituents, chiral enynes, and enynes containing substituted olefins are described in detail. A mechanism involving carbonylation of an intermediate titanacyclopentene has been proposed.

Under the shielding effect of nanomicelles, a sustainable micellar technology for the design and convenient synthesis of ligand-free oxidizable ultrasmall Pd(0) nanoparticles (NPs) and their subsequent catalytic exploration for couplings of water-sensitive acid chlorides in water is reported. A proline-derived amphiphile, PS-750-M, plays a crucial role in stabilizing these NPs, preventing their aggregation and oxidation state changes. These NPs were characterized using 13 C nuclear magnetic resonance (NMR), infrared (IR), and surface-enhanced Raman scattering (SERS) spectroscopy to evaluate the carbonyl interactions of PS-750-M with Pd. High-resolution transmission electron microscopy (HRTEM) and energy-dispersive X-ray spectroscopy (EDX) studies were performed to reveal the morphology, particle size distribution, and chemical composition, whereas X-ray photoelectron spectroscopy (XPS) measurements unveiled the oxidation state of the metal. In the cross-couplings of water-sensitive acid chlorides with boronic acids, the micelle’s shielding effect and boronic acids plays a vital role in preventing unwanted side reactions, including the hydrolysis of acid chlorides under basic pH. This approach is scalable and the applications are showcased in multigram scale reactions.

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