A Multifunctional Pincer Ligand for Cobalt-Promoted Oxidation by N2 O.
Chemistry
; 24(22): 5962-5966, 2018 Apr 17.
Article
en En
| MEDLINE
| ID: mdl-29437249
ABSTRACT
The divalent cobalt complex of the diprotic pincer ligand bis-pyrazolylpyridine, (H2 L)CoCl2 , is dehydrohalogenated twice by LiN(SiMe3 )2 in the presence of PEt3 to give monomeric S=1/2 LCo(PEt3 )2 (1), fully characterized in the solid-state and solution as a square pyramidal monomer with a long axial Co-P bond. This 17-electron species reacts in time of mixing with N2 O to form L2 Co2 (µ-OPEt3 ) (2)+3 OPEt3 , the former the first example of phosphine oxide bridging two transition metals. The same products are formed from O2 , and divalent cobalt persists even in the presence of excess oxidant. Species (2) catalyzes oxygen atom transfer (OAT) for generation of O=PEt3 from PEt3 from either N2 O or O2 . Bridging and terminal cobalt oxo intermediates are suggested, and the electron donor power, and potential redox activity of the dianionic pincer ligand is emphasized.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
Chemistry
Asunto de la revista:
QUIMICA
Año:
2018
Tipo del documento:
Article
País de afiliación:
Estados Unidos