Preparation, Structure, and Ether Cleavage of a Mixed Hapticity Allyl Compound of Calcium

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• 作者：Phillip Jochmann ; Thomas P. Spaniol ; Stephen C. Chmely ; Timothy P. Hanusa ; Jun Okuda
• 刊名：Organometallics
• 出版年：2011
• 出版时间：October 10, 2011
• 年：2011
• 卷：30
• 期：19
• 页码：5291-5296
• 全文大小：826K
• 年卷期：v.30,no.19(October 10, 2011)
• ISSN：1520-6041

文摘

The synthesis, characterization, and decomposition pathway of the 18-crown-6 adduct of bis(allyl)calcium [Ca(畏¹-C₃H₅)(畏³-C₃H₅)(18-crown-6)] (2) are reported. The solid-state structure of adduct 2 features one 蟽- and one 蟺-bonded allyl ligand at the metal center. 2 is the first structurally characterized example of a mononuclear calcium complex bearing a purely 蟽-bound allyl ligand. DFT calculations indicate that [Ca(畏¹-C₃H₅)(畏³-C₃H₅)(18-crown-6)] and [Ca(畏¹-C₃H₅)₂(18-crown-6)] conformations are close in energy. In THF solution, 畏³-allyl ligands are observed exclusively at both ambient temperature and 鈭?5 掳C. 2 undergoes rapid cleavage of the crown ether to give vinyl-terminated alcoholates of different chain length with a half-life of t_1/2 = 2.5 h.