Experimental and Computational Studies on Quadruply Bonded Dimolybdenum Complexes with Terminal and Bridging Hydride Ligands

This contribution focuses on complex [Mo-2(H)(2)(mu-Ad(Dipp2))(2)] (1) and tetrahydrofuran and pyridine adducts [Mo-2(H)(2)(mu-Ad(Dipp2))(2)(L)(2)] (1.thf and 1.py), which contain a trans-(H)Mo strictly equivalent to Mo(H) core (Ad(Dipp2)=HC(NDipp(2))(2); Dipp=2,6-iPr(2)C(6)H(3)). Computational studies provide insights into the coordination and electronic characteristics of the central trans-Mo2H2 unit of 1, with four-coordinate, fourteen-electron Mo atoms and epsilon-agostic interactions with Dipp methyl groups. Small size C- and N-donors give rise to related complexes 1.L but only one molecule of P-donors, for example, PMe3, can bind to 1, causing one of the hydrides to form a three-centered, two-electron (3c-2e) Mo-H -> Mo bond (2.PMe3). A DFT analysis of the terminal and bridging hydride coordination to the Mo strictly equivalent to Mo bond is also reported, along with reactivity studies of the Mo-H bonds of these complexes. Reactions investigated include oxidation of 1.thf by silver triflimidate, AgNTf2, to afford a monohydride [Mo-2(mu-H)(mu-NTf2)(mu-Ad(Dipp2))(2)] (4), with an O,O'-bridging triflimidate ligand.

Automated summary

This study focuses on complex [Mo-2(H)(2)(mu-Ad(Dipp2))(2)] (1) and its adducts with tetrahydrofuran and pyridine. Computational studies provide insights into the coordination and electronic characteristics of the central trans-Mo2H2 unit, as well as the reactivity of the Mo-H bonds in these complexes. Reactions investigated include oxidation of the adducts by silver triflimidate to form a monohydride complex with a bridging triflimidate ligand.