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Homoleptic ceric pyrazolates (pz) Ce(RR’pz)₄ (R = R’ = <i>t</i>Bu; R = R’ = Ph; R = <i>t</i>Bu, R’ = Me) were synthesized by the protonolysis reaction of Ce[N(SiHMe₂)₂]₄ with the corresponding pyrazole derivative. The resulting complexes were investigated in their reactivity toward CO₂, revealing a significant influence of the bulkiness of the substituents on the pyrazolato ligands. The efficiency of the CO₂ insertion was found to increase in the order of <i>t</i>Bu₂pz < Ph₂pz < <i>t</i>BuMepz < Me₂pz. For comparison, the pyrrole-based ate complexes [Ce₂(pyr)₆(<i>µ</i>-pyr)₂(thf)₂][Li(thf)₄]₂ (pyr = pyrrolato) and [Ce(cbz)₄(thf)₂][Li(thf)₄] (cbz = carbazolato) were obtained via protonolysis of the cerous ate complex Ce[N(SiHMe₂)₂]₄Li(thf) with pyrrole and carbazole, respectively. Treatment of the pyrrolate/carbazolate complexes with CO₂ seemed promising, but any reversibility could not be observed.