Abstract

Internal alkynones of the type PhC≡CCOR (R = Ph, Me) undergo thermal isomerization to disubstituted vinylidenes, Ru═C═C(COR)Ph in the coordination sphere of tris(pyrazolyl)borate ruthenium complexes. The treatment of [TpRuCl(PiPr2Me)(MeCN)] and [TpRuCl(iPr2PNHPy)] with NaBArF4 (ArF = 3,5-bis(trifluoromethyl)phenyl) and the corresponding alkynone yields η1-O-ketone complexes as kinetic products. These species are metastable and spontaneously isomerize to disubstituted vinylidenes both in solution and in the solid state. Kinetic studies in solution show that the isomerization rate is first-order in the concentration of the ketone complex, and thus the activation parameters have been obtained from Eyring plots. A concerted sigmatropic 1,2-acyl shift is proposed as the key step. The isomerization in the solid-state has been studied by IR spectroscopy and the results interpreted with the Avrami−Erofeev model. The X-ray structure of a disubstituted vinylidene complex has been determined for the complex [TpRu{═C...

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.