As previously reported, the reaction between W2(NMe2)6 and 2,2′-methylenebis(6-tert-butyl-4-methyl-phenol), HO-CH2-OH, in hydrocarbon solvents leads to W2( μ-H)( μ-NMe2)(η2-O-CH2-O)(η3-O-CH-O)(HNMe2)(NMe2), 1, by oxidative cyclometallation to the ditungsten center. Upon heating 1 to greater than 60°C under dynamic vacuum W2(NMe2)2(η2-O-CH2-O)2,2, is formed with elimination of HNMe2. Compound 2 is proposed to have an ethane-like O2NW≡WO2N core based on NMR data. Addition of HNMe2 to 2 at room temperature converts 2 to 1. The addition of other neutral ligands (pyridine, PMe3) to hydrocarbon solutions of 2 promotes the C-H oxidative addition to the W2 center and the pyridine adduct W2( μ-H)( μ-NMe2)(NMe2)(py)(η2-O-CH2-O)(η3-O-CH-O), 3, has been fully characterized by an X-ray study. Addition of PMe3 to 2 at low temperatures reveals that Lewis base association occurs prior to C-H activation. There is no evidence for an agostic interaction for 2 by NMR or IR spectroscopy.
All Science Journal Classification (ASJC) codes
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry
- Materials Chemistry