Synthesis of Thorium(IV) and Uranium(IV) Salicylaldiminate Pseudo‐Halide Complexes

To explore the coordination chemistry of salicylaldiminate ligands as a non‐cyclopentadienyl ligand framework, we report the synthesis of their Th IV and U IV complexes. Deprotonation of (NC 5 H 4 )N=C(H)(3,5‐ t Bu 2 C 6 H 2 )OH ( 1 ), (NC 9 H 6 )N=C(H)(3,5‐ t Bu 2 C 6 H 2 )OH ( 2 ), and (CH 3 SC 6 H 4 )N=C(H)(3,5‐ t Bu 2 C 6 H 2 )OH ( 3 ) with sodium hydride and the subsequent addition of 0.5 equivalents of [UI 4 (1,4‐dioxane) 2 ] yielded [{(NC 5 H 4 )N=C(H)(3,5‐ t Bu 2 C 6 H 2 )O‐κ 3 ( O , N , N′ )} 2 UI 2 ] ( 4 ), [{(NC 9 H 6 )N=C(H)(3,5‐ t Bu 2 C 6 H 2 )O‐κ 3 ( O , N , N′ )} 2 UI 2 ] ( 5 ), and [{(CH 3 SC 6 H 4 )N=C(H)(3,5‐ t Bu 2 C 6 H 2 )O‐κ 3 ( O , N , S )} 2 UI 2 ] ( 6 ), respectively. The reaction of 3 equivalents of the sodium salt of 1 afforded [{(NC 5 H 4 )N=C(H)(3,5‐ t Bu 2 C 6 H 2 )O‐κ 3 ( O , N , N′ )} 3 U]I 3 ( 7 ). By using [ThCl 4 (dme) 2 ], [{(NC 5 H 4 )N=C(H)(3,5‐ t Bu 2 C 6 H 2 )O‐κ 3 ( O , N , N′ )} 2 ThCl 2 ] ( 8 ) and [{(NC 9 H 6 )N=C(H)(3,5‐ t Bu 2 C 6 H 2 )O‐κ 3 ( O , N , N′ )} 2 ThCl 2 ] ( 9 ) were isolated. The metathesis of both chloride ligands in 9 with NaN 3 led to a rare thorium azide product, [{(NC 9 H 6 )N=C(H)(3,5‐ t Bu 2 C 6 H 2 )O‐κ 3 ( O , N , N′ )} 2 Th(N 3 ) 2 ] ( 10 ). The reaction of 5 with AgOTf (OTf = O 3 SCF 3 ) afforded [{(NC 9 H 6 )N=C(H)(3,5‐ t Bu 2 C 6 H 2 )O‐κ 3 ( O , N , N′ )} 2 U(OTf) 2 ] ( 11 ), and the subsequent reaction of 11 with 2 equivalents of NaN 3 provided [{(NC 9 H 6 )N=C(H)(3,5‐ t Bu 2 C 6 H 2 )O‐κ 3 ( O , N , N′ )} 2 U(N 3 ) 2 ] ( 12 ). The reaction of 5 with 2 equivalents of AgNO 3 produced [{(NC 9 H 6 )N=C(H)(3,5‐ t Bu 2 C 6 H 2 )O‐κ 3 ( O , N , N′ )} 2 U{NO 3 ‐κ 2 ( O , O )} 2 ] ( 13 ). Each complex was characterized by 1 H NMR and IR spectroscopy and, with the exception of 11 , their structures were determined by X‐ray crystallographic analysis.