Preparation and molecular structure of a pyrazolyl–ruthenium complex, Ru{C3H2NN(SO2tol)}(dppe)Cp*

The reaction between RuCl(dppe)Cp* and Me3SiCCC(SiMe3)NNHTs has given the pyrazole derivative (1), which was characterised by a single-crystal X-ray structure determination. Complex 1 is probably formed by attack of the NTs group on the π-complexed desilylated alkyne, with concomitant loss of a proton.