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Title: Intra- and intermolecular interception of a photochemically generated terminal uranium nitride
The photochemically generated synthesis of a terminal uranium nitride species is here reported and an examination of its intra- and intermolecular chemistry is presented. Treatment of the U( iii ) complex L Ar UI(DME) ((L Ar ) 2− = 2,2′′-bis(Dippanilide)- p -terphenyl; Dipp = 2,6-diisopropylphenyl) with LiNIm Dipp ((NIm Dipp ) − = 1,3-bis(Dipp)-imidazolin-2-iminato) generates the sterically congested 3N-coordinate compound L Ar U(NIm Dipp ) ( 1 ). Complex 1 reacts with 1 equiv. of Ph 3 CN 3 to give the U( iv ) azide L Ar U(N 3 )(NIm Dipp ) ( 2 ). Structural analysis of 2 reveals inequivalent N α –N β > N β –N γ distances indicative of an activated azide moiety predisposed to N 2 loss. Room-temperature photolysis of benzene solutions of 2 affords the U( iv ) amide ( N -L Ar )U(NIm Dipp ) ( 3 ) via intramolecular N-atom insertion into the benzylic C–H bond of a pendant isopropyl group of the (L Ar ) 2− ligand. The formation of 3 occurs as a result of the intramolecular interception of the intermediately generated, terminal uranium nitride (L Ar )U(N)(NIm Dipp ) ( 3′ ). Evidence for the formation of 3′ is further bolstered by its intermolecular capture, accomplished by photolyzing solutions of 2 in the presence of an isocyanide or PMe 3 to give (L Ar )U[NCN(C 6 H 3 Me 2 )](NIm Dipp ) ( 5 ) and ( N , C -L Ar *)U(NPMe 3 )(NIm Dipp ) ( 6 ), respectively. These results expand upon the limited reactivity studies of terminal uranium–nitride moieties and provide new insights into their chemical properties.  more » « less
Award ID(s):
1827875
PAR ID:
10148953
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Chemical Science
Volume:
11
Issue:
9
ISSN:
2041-6520
Page Range / eLocation ID:
2381 to 2387
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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