Details

Autor(en) / Beteiligte

• Varela‐Izquierdo, Víctor
• López, José A.
• Bruin, Bas
• Tejel, Cristina
• Ciriano, Miguel A.

Titel

Three‐Coordinate Rhodium Complexes in Low Oxidation States

Ist Teil von

• Chemistry : a European journal, 2020-03, Vol.26 (15), p.3270-3274

Ort / Verlag

Germany: Wiley Subscription Services, Inc

Erscheinungsjahr

2020

Quelle

Wiley Online Library

Beschreibungen/Notizen

• The isolation of simultaneously low‐coordinate and low‐valent compounds is a timeless challenge for preparative chemists. This work showcases the preparation and full characterization of tri‐coordinate rhodium(‐I) and rhodium(0) complexes as well as a rare rhodium(I) complex. Reduction of [{Rh(μ‐Cl)(IPr)(dvtms)}2] (1, IPr=1,3‐bis(2,6‐diisopropylphenyl)imidazolyl‐2‐ylidene; dvtms=divinyltetramethyldisiloxane) with KC8 gave the trigonal complexes K[Rh(IPr)(dvtms)] and [Rh(IPr)(dvtms)], whereas the cation [Rh(IPr)(dvtms)]+ results from their oxidation or by ion of chloride from 1 with silver salts. The paramagnetic Rh0 complex is a unique fully metal‐centered radical with the unpaired electron in the dz2 orbital. The Rh(‐I) complex reacts with PPh3 with replacement of the NHC ligand, and behaves as a nucleophile, which upon reaction with [AuCl(PPh3)] generates the trigonal pyramidal complex [(IPr)(dvtms)Rh‐Au(PPh3)] with a metal–metal bond between two d10 metal centers. Trigonal‐planar rhodium complexes in low oxidation states are feasible by combination of a highly flexible diolefin and a bulky ligand. One‐electron oxidation of the diamagnetic Rh(‐I) complex gives the paramagnetic Rh0 counterpart, a unique metal‐centered radical with the unpaired electron in the dz2 orbital. Code color: Rh (yellow), K (pink), Si (green), O (red), N (blue), C (gray).