Syntheses and crystal structures of two new cationic 3,5-dimethylpyrazole derivatives containing organoiron mixed-sandwiches as substituent groups

Organometallic hydrazines formulated as [(η5-Cp)Fe(η6-p-MeC6H4NHNH2)]+PF6-,Cp=C5H5([1]+PF6-)and[(η5-Cp∗)Fe(η6-C6H5NHNH2)]+PF6-,Cp∗=C5Me5([2]+PF6-), react with 2,4-pentanedione in acetonitrile to afford 3,5-dimethylpyrazole derivatives [3]+PF6-and[4]+PF6-, respectively, that contain the organoiron mixed-sandwich moieties. The new complexes have been fully characterized by elemental analysis and IR, UV–vis and 1H and 13C NMR spectroscopies and authenticated by single crystal X-ray diffraction analysis. Complexes [3]+PF6-(C17H19F6FeN2P)and[4]+PF6-(C21H27F6FeN2P) crystallize in the space group P21/n.

Graphical abstractTwo novel 3,5-Me2-pyrazole derivatives containing the organoiron mixed-sandwich moieties have been synthesized by reaction of the corresponding organometallic hydrazines with 2,4-pentanedione in MeCN. The cationic complexes have been fully characterized by elemental analysis and IR, UV–vis and 1H and 13C NMR spectroscopies and authenticated by single crystal X-ray diffraction analysis.Figure optionsDownload full-size imageDownload as PowerPoint slide