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The metalation/transmetalation strategy using [Zr(NMe2)4] as initial metalating reagent offers an efficient approach to the synthesis of CCC–NHC pincer complexes. Many CCC–NHC pincer complexes have been prepared via this methodology. As efficient as this methodology is, many questions remained as to the mechanism for the process, particularly the requirement of two equivalents of Rh per proligand for good yields. Previously, no intermediates have been reported to shed light on the mechanism. In the process of investigating an intermediate and the mechanism of the metalation/transmetalation methodology, a new mixed valent bimetallic CCC–NHC pincer Rh complex with two chloro ligands bridged between a [(CCC–NHC)Rh(III)] and a [Rh(I)(COD)] fragment was isolated and fully characterized. The investigation of the Rh(III)/Rh(I) bimetallic intermediate in the CCC–NHC pincer metalation/transmetalation methodology led to an improved stoichiometric synthesis of CCC–NHC pincer Rh complexes. It was found that switching the proligand from iodide to chloride counterion obviated the need for an extra equivalent of Rh. The iodide bridged Rh(III)/Rh(I) intermediate was much more stable and prevented further reaction in comparison to the chloride congener. When it was switched to only chloride present the reaction quickly gave efficient, complete transmetalation with only a 1:1 ratio of proligand:Rh.