Journey from Mo−Mo Quadruple Bonds to Quintuple Bonds
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- 作者：Yi-Chou Tsai ; Hong-Zhang Chen ; Chie-Chieh Chang ; Jen-Shiang K. Yu ; Gene-Hsiang Lee ; Yu Wang ; Ting-Shen Kuo
- 刊名：Journal of the American Chemical Society
- 出版年：2009
- 出版时间：September 9, 2009
- 年：2009
- 卷：131
- 期：35
- 页码：12534-12535
- 全文大小：166K
- 年卷期：v.131,no.35(September 9, 2009)
- ISSN：1520-5126
文摘
Heating K4Mo2Cl8 and 2 equiv of Li[RC(NDipp)2] (R = H, Ph; Dipp = 2,6-i-Pr2C6H3) in tetrahydrofuran (THF) at 60 °C gives two paddlewheel type quadruply bonded dimolybdenum complexes, Mo2(μ-Cl)[Cl2Li(OEt2)][μ-η2-RC(N-2,6-i-Pr2C6H3)2]2 (R = H (1), Ph (2)). The Mo−Mo bond lengths of 1 and 2 are 2.0875(4) and 2.0756(8) Å, respectively, indicating typical Mo−Mo quadruple bonds. Reduction of 1 and 2 by two electrons results in the isolation of their corresponding Mo−Mo quintuple bonded complexes, Mo2[μ-η2-RC(N-2,6-i-Pr2C6H3)2]2 (R = H (3), Ph (4)), and the Mo−Mo bond lengths dramatically decrease to 2.0187(9) Å (3) and 2.0157(4) Å (4), a consequence of the formation of the second δ bond and representing the shortest metal−metal bonds beyond the first row elements. The Mo−Mo quintuple bonding characters are corroborated by DFT calculations at the level of BP86/def2-TZVP and BP86/def2-TZVPP.