Uranium Metalla-Allenes with Carbene Imido R2C=UIV=NR′ Units (R=Ph2PNSiMe3; R′=CPh3): Alkali-Metal-Mediated push–pull effects with an Amido Auxiliary

Lu, Erli; Tuna, Floriana; Lewis, William; Kaltsoyannis, Nikolas; Liddle, Stephen T.

Abstract

We report uranium(IV)-carbene-imido-amide metalla-allene complexes [U(BIPMTMS)(NCPh3)(NHCPh3)(M)] (BIPMTMS=C(PPh2NSiMe3)2; M=Li or K) that can be described as R2C=U=NR′ push–pull metalla-allene units, as organometallic counterparts of the well-known push–pull organic allenes. The solid-state structures reveal that the R2C=U=NR′ units adopt highly unusual cis-arrangements, which are also reproduced by gas-phase theoretical studies conducted without the alkali metals to remove their potential structure-directing roles. Computational studies confirm the double-bond nature of the U=NR′ and U=CR2 interactions, the latter increasingly attenuated by potassium then lithium when compared to the hypothetical alkali-metal-free anion. Combined experimental and theoretical data show that the push–pull effect induced by the alkali metal cations and amide auxiliary gives a fundamental and tunable structural influence over the C=UIV=N units.

Citation

Lu, E., Tuna, F., Lewis, W., Kaltsoyannis, N., & Liddle, S. T. (2016). Uranium Metalla-Allenes with Carbene Imido R2C=UIV=NR′ Units (R=Ph2PNSiMe3; R′=CPh3): Alkali-Metal-Mediated push–pull effects with an Amido Auxiliary. Chemistry - A European Journal, 22(33), 11554-11558. https://doi.org/10.1002/chem.201602603

• Journal Article Type: Article
• Acceptance Date: Jul 12, 2016
• Online Publication Date: Jul 12, 2016
• Publication Date: Aug 1, 2016
• Deposit Date: Sep 28, 2017
• Publicly Available Date: Sep 28, 2017
• Journal: Chemistry - A European Journal
• Print ISSN: 0947-6539
• Electronic ISSN: 1521-3765
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 22
• Issue: 33
• Pages: 11554-11558
• DOI: https://doi.org/10.1002/chem.201602603
• Public URL: https://nottingham-repository.worktribe.com/output/797814
• Publisher URL: http://onlinelibrary.wiley.com/doi/10.1002/chem.201602603/abstract
• Additional Information: This is the peer reviewed version of the following article: E.Lu, F.Tuna, W.Lewis, N.Kaltsoyannis, S.T. Liddle, Chem. Eur. J. 2016, 22, 11554, which has been published in final form at doi:10.1002/chem.201602603. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.