Reaction of 2-vinylpyrazine with Ru3(CO)12 results in multiple C–H bond activations to afford penta- and octa-ruthenium clusters, Ru5(CO)15(μ5-C4H2N2CH![[double bond, length as m-dash]](http://www.rsc.org/images/entities/char_e001.gif)
CH)(μ-H)2 (2) and Ru8(CO)24(μ7-C4H2N2CHC)(μ-H)3 (3), in which a Ru3 sub-unit is linked to Ru2 and Ru5 centres via di- and tri-metalated 2-vinylpyrazine ligands, exhibiting novel coordination modes including the loss of ring aromaticity in 2. The bonding of 2 and the mechanism for the fluxional behaviour of the hydrides have been examined by electronic structure calculations.
![Graphical abstract: New molecular architectures containing low-valent cluster centres with di- and trimetalated 2-vinylpyrazine ligands: synthesis and molecular structures of Ru5(CO)15(μ5-C4H2N2CH [[double bond, length as m-dash]] CH)(μ-H)2 and Ru8(CO)24(μ7-C4H2N2CH [[double bond, length as m-dash]] C)(μ-H)3](http://hg.y866.cn/compound/lib/scimg/usr/1/C9RA03841H.jpg)
