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Preparation of 6-aminocyclohepta-2,4-dien-1-one Derivatives via Tricarbonyltroponeiron
Published on: August 12, 2019
Trivalent rare-earth metal cyclic (alkyl)(amino)carbene complexes
Yuyuan Xiao1, Ziyu Liu1, Jiefeng Liang1
1Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China. wlhuang@pku.edu.cn.
Abstract:
Coordination chemistry of cyclic (alkyl)(amino)carbene (CAAC) ligands has blossomed in recent years, exemplified by their strong σ-donating and π-accepting ability. However, trivalent rare-earth metal CAAC complexes remain elusive. By using M(CH2SiMe3)3(THF)2 (M = Sc, Y and Lu) as precursors, we synthesized mono CAAC coordinated rare-earth metal trisalkyl complexes, (RCAAC)M(CH2SiMe3)3 (R = Me and Et, M = Sc, Y and Lu). In addition, when MI3(Et2O) (M = Y and Yb) were employed as metal precursors, bis(CAAC)-stabilized rare-earth metal triiodide complexes (MeCAAC)2MI3 (M = Y and Yb) could be obtained. All new compounds were characterized by X-ray crystallography, elemental analysis and NMR spectroscopy. Density functional theory calculations were conducted for these rare-earth metal CAAC complexes to gain insight into their electronic structures and bonding interactions. The bonding analysis unveils that the CAAC ligands act as σ donors to trivalent rare-earth metal ions and may be involved in π-bonding upon reduction.
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