Synthesis and Characterization of an f-Block Terminal Parent Imido [U═NH] Complex: A Masked Uranium(IV) Nitride

King, David M.; McMaster, Jonathan; Tuna, Floriana; McInnes, Eric J.L.; Lewis, William; Blake, Alexander J.; Liddle, Stephen T.

Abstract

Deprotonation of [U(TrenTIPS)(NH2)] (1) [TrenTIPS = N(CH2CH2NSiPri3)3] with organoalkali metal reagents MR (M = Li, R = But; M = Na−Cs, R = CH2C6H5) afforded the imido-bridged dimers [{U-(TrenTIPS)(μ-N[H]M)}2] [M = L −Cs (2a−e)]. Treatmentof 2c (M = K) with 2 equiv of 15 crown-5 ether (15C5) afforded the uranium terminal parent imido complex [U(TrenTIPS)(NH)][K(15C5)2] (3c), which can also be viewed as a masked uranium(IV) nitride. The uranium−imido linkage was found to be essentially linear, and theoretical calculations suggested σ2π4 polarized U−N multiple bonding. Attempts to oxidize 3c to afford the neutral uranium terminal parent imido complex [U(TrenTIPS)(NH)] (4) resulted in spontaneous disproportionation to give 1 and the uranium−nitride complex [U(TrenTIPS)(N)] (5); this reaction is a new way to prepare the terminal uranium−nitride linkage and was calculated to be exothermic by −3.25 kcal mol−1.

Citation

King, D. M., McMaster, J., Tuna, F., McInnes, E. J., Lewis, W., Blake, A. J., & Liddle, S. T. (2014). Synthesis and Characterization of an f-Block Terminal Parent Imido [U═NH] Complex: A Masked Uranium(IV) Nitride. Journal of the American Chemical Society, 136(15), 5619-5622. https://doi.org/10.1021/ja502405e

• Journal Article Type: Article
• Acceptance Date: Mar 12, 2014
• Online Publication Date: Apr 8, 2014
• Publication Date: Apr 16, 2014
• Deposit Date: Aug 17, 2016
• Publicly Available Date: Aug 17, 2016
• Journal: Journal of the American Chemical Society
• Print ISSN: 0002-7863
• Electronic ISSN: 1520-5126
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 136
• Issue: 15
• Pages: 5619-5622
• DOI: https://doi.org/10.1021/ja502405e
• Public URL: https://nottingham-repository.worktribe.com/output/727643
• Publisher URL: http://pubs.acs.org/doi/abs/10.1021/ja502405e
• Contract Date: Aug 17, 2016