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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. 

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. 

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