Carbenosmium‐Komplexe durch Zweifachmetallierung von Alkoxyalkyl‐ und Aminoalkylphosphanen

Abstract

Die Umwandlung einer Methoxy‐oder Methylamino‐Gruppe in einen Carben‐Liganden gelingt, wenn diese Teil eines Phosphans sind, So lassen sich in einer ergiebigen Eintopfsynthese die Komplex 1 und 2 aus OsCl3 · 3H2O bzw.[OsCl2(PPh3)3] und den phosphanen iPr2PCH2CH2Y (YOMe bzw. NMe2)herstellen. Mit dem Phosphan iPr2PCH2CO2Me kann ein Osmium(II)‐Komplex isoliert werden, der mit Phenylacetylen quantitativ zum Vinylidenkomplex 3 reagiert.

Osmium(II) and Osmium(IV) Complexes with Phosphane–Ethers, –Esters, and –Amines as Mono‐ and Bidentate Ligands

“…While the osmium(IV) compounds 3, 4 as well as the osmium(II) complexes 7, 8 2 OMe}] by double metalation of the methoxy group of the phosphane. [5] The phosphane-amine iPr 2 PCH 2 -CH 2 NMe 2 behaves similarly.…”

Hydrido‐Osmium(II), ‐Osmium(IV) and‐Osmium(VI) Complexes with Functionalized Phosphanes as Ligands

“…We note that the chemistry of a manifold of osmium and ruthenium compounds with phosphane ethers, phosphane esters and phosphaneamines as ligands has recently been investigated in our laboratory as well as by others. [7,8] As a continuation of our earlier work, we report here the synthesis of a series of mono-, di-, tetra-and hexahydrido-…”

Synthesis and Reactivity of an Aminocarbene Osmium Complex Formed by Double C–H Activation of a NCH3 Unit

“…We note that the molecular structure of the related oxocarbene complex cis,cis-[OsCl 2 {κ 2 (C,P)-CHOCH 2 CH 2 PiPr 2 }{κ 2 (P,O)-iPr 2 -PCH 2 CH 2 OMe}] was determined crystallographically; the result confirmed that the two PiPr 2 units as well as the two chloro ligands are cis-disposed. [6] Scheme 1.…”

“…As previously described, the oxocarbene-osmium ( [6] Since the yield of the product was significantly higher with OsCl 3 ·3H 2 O as the precursor, we first treated this compound with iPr 2 PCH 2 CH 2 NMe 2 . However, the reaction of OsCl 3 ·3H 2 O with iPr 2 PCH 2 CH 2 NMe 2 in 2-propanol under reflux gave a mixture of products which, based on the spectroscopic data, contained only about 40-50 % of the aminocarbene complex 2.…”

“…[4] The seemingly more simple approach to obtain, for example, [ [5] led to a surprising result: instead of the expected product the Fischer-type oxocarbene-osmium(II) complex cis,cis-[OsCl 2 {κ 2 (C,P)-CHOCH 2 CH 2 PiPr 2 }{κ 2 -(P,O)-iPr 2 PCH 2 CH 2 OMe}] was obtained. [6] In this paper we report that the phosphaneamine iPr 2 PCH 2 CH 2 NMe 2 behaves similar to the phosphane ether iPr 2 PCH 2 CH 2 OMe and affords upon treatment with 3 ] an aminocarbene-osmium(II) derivative. The reactivity of this complex toward some nucleophilic substrates illustrates the inert nature of the carbene-osmium bond.…”