4‐Ethynylpyridine as a Bridging Moiety in Mixed Rh/Re Complexes

Abstract

Abstract A paramagnetic, dimeric Rh III Rh II complex of the formula [Rh 2 (form) 4 (C≡CC 5 H 4 N)] ( 1 ) [form = N , N′ ‐di‐ p ‐tolylformamidinate; C 5 H 4 N = pyridyl (py)] has been synthesized and used as starting material to prepare heterotrimetallic complexes of composition [Rh 2 (form) 4 (C≡Cpy){Re(CO) 3 (bipy)}][OS(=O) 2 CF 3 ] ( 2 ) and [Rh 2 (form) 4 (C≡Cpy){Re(CO) 3 ( t bu 2 bipy)}][OS(=O) 2 CF 3 ] ( 3 ). These complexes have been examined by vibrational spectroscopy, EPR spectroscopy, thermogravimetry and cyclic voltammetry. They are heat‐stable and can be handled in air without problems. The observed interactions between the Rh 2 and the Re subunits, however, are weak, and a significant charge transfer does not seem to take place. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)