Quintuple binding

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The structure of [CrC 6 H 3 -2,6- (C 6 H 3 -2,6- (CHMe 2 ) 2 ) 2 ] 2

A five-fold bond is a form of chemical bond between two atoms that is mediated via electron pairs ( electron pair bond ). Five pairs of binding electrons between the atoms ensure that the molecule on top of them holds together .

Only in November 2005 by Philip Power et al. discovered quintuple bond consists of a metal-metal bond of the compound Ar-Cr 2 -Ar (dark red crystals, thermally stable up to 200 ° C) with an aryl moiety (Ar = terphenyl - Ligand C 6 H 3 -2,6- ( C 6 H 3 -2.6- i Pr 2 ) 2 ).

The bond consists of the following individual bonds:

The five-fold bond thus only differs from the four- fold bond by an additional (degenerate) δ bond .

In addition, five-fold bonds based on N-donor ligands are now also known.

literature

  • Laura Gagliardi & Björn O. Roos: "Quantum chemical calculations show that the uranium molecule U 2 has a quintuple bond", Nature , 433, pp. 848-851 (February 24, 2005); doi : 10.1038 / nature03249 ; PMID 15729337 .

Individual evidence

  1. ↑ Tailuan Nguyen, Andrew D. Sutton, Marcin Brynda, James C. Fettinger, Gary J. Long, Philip P. Power, Synthesis of a Stable Compound with Fivefold Bonding Between Two Chromium (I) Centers , Science 4 , November 2005 , Vol . 310 no. 5749 pp. 844-847. doi : 10.1126 / science.1116789 .
  2. ↑ Sylvester Ndambuki, Tom Ziegler, Analysis of the Putative Cr – Cr Quintuple Bond in Ar′CrCrAr ′ (Ar ′ = C 6 H 3 -2.6 (C 6 H 3 -2.6-Pr i 2 ) 2 ) Based on the Combined Natural Orbitals for Chemical Valence and Extended Transition State Method , Inorg. Chem. 2012 , 51 (14), pp. 7794-7800, doi : 10.1021 / ic300824u .
  3. ↑ Yu-Lun Huang, Duan-Yen Lu, Hsien-Cheng Yu, Jen-Shiang K. Yu, Chia-Wei Hsu, Ting-Shen Kuo, Gene-Hsiang Lee, Yu Wang, Yi-Chou Tsai, Stepwise Construction of the Cr-Cr Quintuple Bond and Its Destruction upon Axial Coordination , Angewandte Chemie International Edition , 2012 , Volume 51 , Issue 31, pp. 7781-7785, doi : 10.1002 / anie.201202337 .

See also