1,2-Addition or Enolization? Variable Reactivity of a Cerium Acetylide Complex toward Carbonyl Compounds

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• 作者：Jee Eon Kim ; Alexander V. Zabula ; Patrick J. Carroll ; Eric J. Schelter
• 刊名：Organometallics
• 出版年：2016
• 出版时间：June 27, 2016
• 年：2016
• 卷：35
• 期：12
• 页码：2086-2091
• 全文大小：406K
• 年卷期：0
• ISSN：1520-6041

文摘

The reactions of the cerium alkyne complex bearing 2,6-bis(dimethylamino)-4-methylphenolate supporting ligands (bdmmp) and a terminal acetylide moiety, Na[Ce(C≡CPh)(bdmmp)₃] (1), with benzaldehyde and a family of enolizable ketones led to different products depending on the acidity of the parent carbonyl compound. The reactions of 1 with benzaldehyde, acetone, benzylideneacetone, or 1,1-diphenylacetone (pK_a^DMSO = 26.5–19.4) gave the products of nucleophilic addition of type Na[Ce(O-CR₂-C≡CPh)(bdmmp)₃] featuring a new C–C bond. In contrast, the reaction of 1 with β-tetralone (pK_a^DMSO = 17.6) resulted in the enolization and deprotonation of β-tetralone with subsequent replacement of the acetylide ligand at the cerium ion by the enolate. Molecular structures for the cerium products were determined by X-ray diffraction studies, providing valuable information about the performance of organocerium reagents.