Hydride complexes 8 readily reacts with olefins. A clean consumption of hydrides in 8 was observed within minutes upon the addition of 4-allylanisole (1a). The analysis of this reaction with IR and NMR spectroscopy indicates the formation of the dicarbonyl Mn-alkyl species. Namely, the IR spectrum (Figure ) indicates the consumption of 8 and formation of two new bands at 1903, 1828 cm -1 typical of dicabonyl complexes. In the absence of the hydride resonance in the NMR spectrum, this suggests that reaction of 8 with olefin leads to the formation of metal-alkyl complexes with N donor group reattaching to the Mn center. As expected, the gradual production of 2a was then detected in 1 H NMR upon the heating the reaction mixture to 60 °C (see Figure ). This observation of hydride transfer suggests that Mn-7 isomerizes olefins via the alkyl mechanism. Since we observe no further change in the NMR spectrum, we assume that the metal alkyl complexes likely represent the resting states in this transformation as was earlier proposed for the high-spin cobalt(II) system by Wiex, Holland and co-workers. 10b Table . Bond length of Mn-N for selected Mn complexes in the solid state calculated from X-Ray data.