Phosphine-Induced Ancillary Ligand Orthometalation at a Tantalum−Tantalum Double Bond

The dinuclear tantalum tetrahydride complexes (RPh[NPN]Ta)2(μ-H)4 (RPh[NPN] = (PhNSiMe2CH2)2PR; R = Ph, Cy) promote the asymmetric activation of molecular nitrogen to form (RPh[NPN]Ta)2(μ-η1:η2-N2)(μ-H)2. The coordinatively unsaturated dinuclear dihydride, (RPh[NPN]Ta)2(μ-H)2, has been proposed as t...

Full description

Saved in:
Bibliographic Details
Published in:Organometallics 2005-05, Vol.24 (11), p.2606-2611
Main Authors: Shaver, Michael P, Fryzuk, Michael D
Format: Article
Language:English
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The dinuclear tantalum tetrahydride complexes (RPh[NPN]Ta)2(μ-H)4 (RPh[NPN] = (PhNSiMe2CH2)2PR; R = Ph, Cy) promote the asymmetric activation of molecular nitrogen to form (RPh[NPN]Ta)2(μ-η1:η2-N2)(μ-H)2. The coordinatively unsaturated dinuclear dihydride, (RPh[NPN]Ta)2(μ-H)2, has been proposed as the reactive intermediate, with a tantalum−tantalum double bond storing four electrons with which to reduce N2. Efforts to trap (CyPh[NPN]Ta)2(μ-H)2 with excess PMe3 at low temperatures promoted the formation of a green product, proposed to be (CyPh[NPN]Ta(PMe3))2(μ-H)2. Attempts to isolate this product promoted the orthometalation of an ancillary ligand N−Ph ring, forming Addition of 1 equiv of PMe3 to (PhPh[NPN]Ta)2(μ-H)4 immediately produced the analogous orthometalation derivative,
ISSN:0276-7333
1520-6041
DOI:10.1021/om050045e