Metallorganische Verbindungen der Lanthanoide, 91[1] Carben‐Addukte des zweiwertigen Samariums und Ytterbiums

Organometallic Compounds of the Lanthanides, 91[1]. - Carbene Complexes of Divalent Samarium and Ytterbium (Imidazol-2-ylidene)lanthanide adducts (C5Me4Et)2Sm–CN-(iPr)CMeCMeN(iPr) (5b), (C5Me5)2Yb–CN(Me)CMeCMeN(Me) (6a), (C5Me5)2Yb–CN(iPr)CMeCMeN(iPr) (6b), and (C5H3tBu2)2Yb–CN(Me)CMeCMeN(Me) (7a) are obtained from 1,3,4,5-tetramethyl-imidazol-2-ylidene (4a) or 1,4-diisopropyl-2,3-dimethylimidazol-2-ylidene (4b) and (C5Me4Et)2Sm(THF) (1), (C5Me5)2Yb(THF) (2), or (C5H3-tBu2)2Yb(THF) (3). The molecular structure of the ytterbium carbene complex 7a has been determined by X-ray diffraction.