In:
Chemistry – A European Journal, Wiley, Vol. 23, No. 12 ( 2017-02-24), p. 2950-2959
Abstract:
The reactivity of terminal uranium(V/VI) nitrides with CE 2 (E=O, S) is presented. Well‐defined C=E cleavage followed by zero‐, one‐, and two‐electron redox events is observed. The uranium(V) nitride [U(Tren TIPS )(N)][K(B15C5) 2 ] ( 1 , Tren TIPS =N(CH 2 CH 2 NSi i Pr 3 ) 3 ; B15C5=benzo‐15‐crown‐5) reacts with CO 2 to give [U(Tren TIPS )(O)(NCO)][K(B15C5) 2 ] ( 3 ), whereas the uranium(VI) nitride [U(Tren TIPS )(N)] ( 2 ) reacts with CO 2 to give isolable [U(Tren TIPS )(O)(NCO)] ( 4 ); complex 4 rapidly decomposes to known [U(Tren TIPS )(O)] ( 5 ) with concomitant formation of N 2 and CO proposed, with the latter trapped as a vanadocene adduct. In contrast, 1 reacts with CS 2 to give [U(Tren TIPS )(κ 2 ‐CS 3 )][K(B15C5) 2 ] ( 6 ), 2 , and [K(B15C5) 2 ][NCS] ( 7 ), whereas 2 reacts with CS 2 to give [U(Tren TIPS )(NCS)] ( 8 ) and “S”, with the latter trapped as Ph 3 PS. Calculated reaction profiles reveal outer‐sphere reactivity for uranium(V) but inner‐sphere mechanisms for uranium(VI); despite the wide divergence of products the initial activation of CE 2 follows mechanistically related pathways, providing insight into the factors of uranium oxidation state, chalcogen, and NCE groups that govern the subsequent divergent redox reactions that include common one‐electron reactions and a less‐common two‐electron redox event. Caution, we suggest, is warranted when utilising CS 2 as a reactivity surrogate for CO 2 .
Type of Medium:
Online Resource
ISSN:
0947-6539
,
1521-3765
DOI:
10.1002/chem.201605620
Language:
English
Publisher:
Wiley
Publication Date:
2017
detail.hit.zdb_id:
1478547-X
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