Diamido-Ether Actinide Complexes as Catalysts for the Intramolecular Hydroamination of Aminoalkenes

The synthesis and characterization of a series of new diamido-thorium(IV) and diamido-uranium(IV) halide and alkyl complexes supported by three different diamido-ether ligands are reported. Reaction of ThCl 4 ·2DME with [(RNSiMe 2 ) 2 O]Li 2 ([ R NON]Li 2 ) in DME when R = t Bu gives [ t Bu NON]ThCl 5 Li 3 ·DME ( 1 ), when R = i Pr 2 Ph in diethyl ether [ i Pr 2 Ph NON]ThCl 3 Li·DME ( 3 ) is prepared. Reaction of UCl 4 with [ i Pr 2 Ph NON]Li 2 in diethyl ether gives {[ i Pr 2 Ph NON]UCl 2 } 2 ( 4 ). Reaction of ThCl 4 ·2DME with Li 2 [( i Pr 2 PhNCH 2 CH 2 ) 2 O] ([ i Pr 2 Ph NCOCN]Li 2 ) in DME gives [ i Pr 2 Ph NCOCN]ThCl 2 ·DME ( 5 ). The addition of 2 equiv of LiCH 2 SiMe 3 to 1 and 5 resulted in salt- and base-free [ t Bu NON]Th(CH 2 SiMe 3 ) 2 ( 7 ) and [ i Pr 2 Ph NCOCN]Th(CH 2 SiMe 3 ) 2 ( 9 ), respectively. Complexes 1, 3, 4, 7, and 9, as well as previously reported {[ t Bu NON]UCl 2 } 2 ( 2 ), [ t Bu NON]U(CH 2 SiMe 3 ) 2 ( 6 ), and [ i Pr 2 Ph NCOCN]U(CH 2 SiMe 3 ) 2 ( 8 ) were examined as catalysts for the intramolecular hydroamination of a series of aminoalkenes. Complexes 6 – 9 were shown to facilitate the formation of 2-methyl-4,4-diphenylpyrrolidine from 2,2-diphenyl-1-amino-4-pentene at room temperature. For 9, this reaction occurs in less than 15 min, while for other dialkyls 6 – 8, the reaction takes less than 2 h. Dihalides 1 and 2 facilitated the same reaction at 60 °C in 4 h, while 3 and 4 showed no activity under the same conditions. Dialkyl complexes 7 – 9 were examined for further reactivity with different substrates. The uranium dialkyl 8 was more active than 7 and 9 for the cyclization of 2,2-diphenyl-1-amino-5-hexene and 2,2-diphenyl-1-amino-6-heptene, as well as more active in the cyclization of N -methyl-2,2-diphenyl-1-amino-4-pentene, a secondary amine. All three dialkyls became less active when the steric bulk of the gem -substituents was decreased from diphenyl to cyclopentyl; reactivity further decreased when the steric bulk of the substituents was decreased further to hydrogen.

Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.