ISSN:
0009-2940
Keywords:
Cationic amido osmium(II) complexes, synthesis from dichloro metal precursor and primary amines
;
Os-N double bond
;
Aldimino(hydrido)osmium(II) complex, formation by β1-hydride migration
;
Amino(chloro)osmium(II) complex, preparation by protonation of an amido derivate
;
Dinuclear imidoosmium complex, presence of a Os2N2 four-membered ring
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Carbene-Type Amidoosmium Complexes with an Os—N Double Bond: Synthesis, Structure and Reactivity of [(Mes)Os(=NHR)(PiPr3)]PF6*The reaction of [(Mes)Os(PiPr3)Cl2] (1) (Mes=1,3,5-C6H3Me3) with primary amines RNH2 (R=Ph, Me, Et) in acetone/water (1:1) gives, after addition of KPF6, the amidoosmium(II) complexes [(Mes)Os(=NHR)(PiPr3)]PF6 (2-4) in 60-80% yield. From 1 and Et2NH, the chloro(hydrido)compound [(Mes)1-OsH(PiPr3)Cl] (5) is formed. The X-ray structural analysis of 2 reveals that the geometry around the osmium atom is trigonalplanar (with the midpoint of the mesitylene ring as one coordination site) and that the Os—N distance of 1.923(4) Å is in agreement with an Os—N double bond. Thermolysis of 4 (R=Et) at 165°C leads to the formation of the aldimino(hydrido)osmium complex [(Mes)OsH(NH=CHMe)(PiPr3)]PF6 (6) by β1-hydride migration from the NCH2 carbon atom to the metal atom. Protonation of 3 (R=Me) with HCl gives the amine complex [(Mes)Os(NH2Me)(PiPr3)Cl]PF6 (7), whereas on treatment of 3 and 4 with CD3NO2 the deuterated derivatives [(Mes)Os(=NDR)(PiPr3)]PF6 ([D1]-3, [D1]-4) are almost quantitatively formed. Compound 2 (R=Ph) reacts with KOtBu by proton abstraction and phosphane elimination to give the dinuclear imidoosmium complex [(Mes)2Os2(μ1-NPh)2] (8).
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19931260619
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