Mo-catalyzed cross-metathesis reaction of propynylferrocene

Catalysts formed in situ from [Mo(CO)(6)] and halophenols in dichloromethane efficiently promote cross metathesis reactions of (prop-1-yn-1-yl)ferrocene with various functionalized alkynes to give the corresponding alkynylferrocenes with good selectivity and yields. Optimization of the reaction conditions by changing the phenol component has been carried out, revealing a critical influence of the phenol structure on the reaction yield. The structures Of Selected compounds were determined by single-crystal X-ray diffraction, and the results (particularly the crystal packing) were correlated with DFT calculations. In addition, the series of alkynes 4-XC6H4C CFc (Fc = ferrocenyl) differing by the substituent X was studied by electrochemical methods, manifesting a good correlation between the redox potential of the ferrocene/ferrocenium couple and the Hammett sigma(p) constants of the remote substituents X. ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008).