Unexpected formation of nitroso-chelated cyclic η1-acylruthenium(II) complex, an effective catalysts for transfer hydrogenation reaction

• Published in: Journal of organometallic chemistry Vol. 867; pp. 359 - 366
• Main Authors: Mukherjee, Nirmalya, Gawin, Rafał, Czarnocki, Stefan J., Gajda, Roman, Malińska, Maura, Woźniak, Krzysztof, Kajetanowicz, Anna, Grela, Karol
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.07.2018
• Subjects: Cycloisomerization; Olefin metathesis; Racemisation; Ring opening metathesis polymerization (ROMP); Ruthenium; Transfer hydrogenation; Transfer hydrogenation; Ring opening metathesis polymerization (ROMP); Racemisation; Cycloisomerization; Ruthenium; Olefin metathesis
• ISSN: 0022-328X; 1872-8561
• DOI: 10.1016/j.jorganchem.2018.01.035

Reaction of commercial ruthenium complexes M31 and M20 with 2-nitrostyrene gave a new nitroso-chelated cyclic η1-acyl ruthenium(II) complexes Ru-4 and Ru-6 respectively instead of expected Hoveyda-Grubbs type (pre)catalyst Ru-3. New complexes were characterized by means of standard analytical techniques and their crystallographic structure has been confirmed by X-ray structural analysis. It was found that Ru-4 and Ru-6 do not exhibit any activity in standard metathesis reactions. However, a dramatic increase of activity was observed upon treatment with (trimethylsilyl)diazomethane, allowed for the successful application of Ru-4 in ROMP of endo,exo-bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid dimethyl ester. Moreover, such complexes can be effective catalysts of transfer hydrogenation of ketones as well as cycloisomerization reactions. Unexpected ruthenium complexes for transfer hydrogenation, cycloisomerization, and ring opening metathesis polymerization. [Display omitted] •Nitroso- chelated acylruthenium complexes were prepared and fully characterized.•The unique structure of the complexes has been confirmed by X-ray structural analysis.•Ru-complex exhibit good activity in transfer hydrogenations of aromatic ketones.•Nitroso- chelated acylruthenium complexes catalyze ROMP in the presence of (trimethylsilyl)diazomethane.