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Alkene hydroboration provides a convenient route to generate organoborane synthons and recent efforts to develop catalysts for this and many other organic transformations have involved a shift to Earth-abundant first row transition metals. Herein, we report the synthesis of a new bench-stable CoII precatalyst, (PPCF3P)CoI2 (1), which was found to function as a highly active alkene hydroboration catalyst in the presence of an activator. The substrate scope was probed through exploring a collection of electronically and sterically distinct alkenes with a wide range of substitution patterns and functional groups. A single species is spectroscopically observed during catalysis, and activation of the CoII precatalyst with KBEt3H in the presence of styrene and in the absence of HBpin affords this species, (PPCF3P)Co(h2-styrene)H (2), which has been isolated, characterized, and demonstrated to function as an active catalyst for alkene hydroboration in the absence of additional activators. A plausible mechanism involving a CoI-hydride active species is proposed based on catalytic and stoichiometric experiments. 

A (PNNP)Fe^IIcomplex is shown to catalyze the dimerization of terminal alkynesviaa metal–ligand cooperative mechanism. 

Here we report the synthesis and characterization of diiron complexes containing triaryl N₄and N₂S₂ligands derived fromo-phenylenediamine. 

Dehydrogenation of the ligand backbone of a bis(amido)bis(phosphine) Co complex is achieved through hydrogen atom abstraction. The new unsaturated backbone of the tetradentate ligand renders the ligand in the resulting Co complex redox-active. 

A Co(II) complex, (PPHP)CoI2, was synthesized and evaluated as a precatalyst for the hydrogenation of terminal alkenes under mild conditions (1 atm H2, ambient temperature) using KBEt3H as an activator. This catalytic system was found to be active for terminal alkene substrates, including 1,1′-disubstituted alkenes, and to exhibit modest air and moisture stability. A preliminary investigation into substrate scope and functional group tolerance was performed. Upon the completion of catalytic reactions, the sole metal complex observed was identified as the dimeric species [(PPP)CoH]2 suggesting that the catalytically active species may be a cobalt hydride monomer.