Disclosed is a method for preparing an organic carboxylic ester by using a combined catalyst of an aryl bidentate phosphine ligand. The method includes subjecting a terminal olefin, carbon monoxide, and an alcohol to a hydroesterification reaction in the presence of a combined catalyst of a palladium compound, an aryl bidentate phosphine ligand, and an acidic additive, to generate an organic carboxylic ester having one more carbon atom than the terminal olefin.

Provided are a ligand compound having Formula 1, which exhibits high catalytic activity while exhibiting high 1-hexene and 1-octene selectivity, thereby allowing ethylene oligomerization to be achieved with excellent efficiency, an organic chromium compound, a catalyst composition including the organic chromium compound, and a method for oligomerizing ethylene by using the same;

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Embodiments of the present disclosure relate to methods, compositions, and systems for proximity-based, photoactivated labeling of molecules. Molecules may be labeled via activation of a ligated photocatalyst capable of transmitting energy to a proximal biomolecular labeling agent. Depending on the activated half-life and diffusion coefficient of the labeling agent, molecules within a particular vicinity of the ligated photocatalyst may be labeled but molecules outside the vicinity will not be labeled.

The present invention relates to air stable, binary Ni(0)-olefin complexes and their use in organic synthesis.