C≡N and N≡O Bond Cleavages of Acetonitrile and Nitrosyl Ligands at a Dimolybdenum Center to Render Ethylidyne and Acetamidinate Ligands

M Angeles Alvarez; M Esther García; Daniel García-Vivó; Ana M Guerra; Miguel A Ruiz

doi:10.1021/acs.inorgchem.3c03697

C≡N and N≡O Bond Cleavages of Acetonitrile and Nitrosyl Ligands at a Dimolybdenum Center to Render Ethylidyne and Acetamidinate Ligands

Inorg Chem. 2024 Feb 19;63(7):3207-3211. doi: 10.1021/acs.inorgchem.3c03697. Epub 2024 Feb 2.

Authors

M Angeles Alvarez¹, M Esther García¹, Daniel García-Vivó¹, Ana M Guerra¹, Miguel A Ruiz¹

Affiliation

¹ Departamento de Química Orgánica e Inorgánica, Instituto Universitario de Química Organometálica "Enrique Moles", Universidad de Oviedo, E33071 Oviedo, Spain.

Abstract

Extended reduction of [Mo₂Cp₂(μ-Cl)(μ-P^tBu₂)(NO)₂] (1) with Na(Hg) in acetonitrile (MeCN) at room temperature resulted in an unprecedented full cleavage of the C≡N bond of a coordinated MeCN molecule to yield the vinylidene derivative Na[Mo₂Cp₂(μ-P^tBu₂)(μ-CCH₂)(NO)₂], which upon protonation with (NH₄)PF₆ gave the ethylidyne complex [Mo₂Cp₂(μ-P^tBu₂)(μ-CMe)(NO)₂] [Mo1-Mo2 = 2.9218(2) Å] in a selective and reversible way. Controlled reduction of 1 at 273 K yielded instead, after protonation, the 30-electron acetamidinate complex [Mo₂Cp₂(μ-P^tBu₂)(μ-κN:κN'-HNCMeNH)(μ-NO)]PF₆ [Mo1-Mo2 = 2.603(2) Å], in a process thought to stem from the paramagnetic MeCN-bridged intermediate [Mo₂Cp₂(μ-P^tBu₂)(μ-NCMe)(NO)₂], followed by a complex sequence of elementary steps including cleavage of the N≡O bond of a nitrosyl ligand.