Lutetium‐Methanediide‐Alkyl Complexes: Unique Reactivity toward Carbodiimide and Pyridine.

We present the reactivity of four‐coordinate lutetium‐methanediide‐alkyl complexes 1 and 2 ((BODDIR)Lu2(CH2SiMe3)2(µ2‐CHSiMe3)(THF)2, R = iPr (1), R = Et (2)). The reaction of 2 with N,N‐diisopropylcarbodiimide (iPrN=C=NiPr) afforded a nucleophilic adduct 3 through insertion of three molecules of iPrN=C=NiPr into the Lu‐µ2‐CHSiMe3 or Lu‐CH2SiMe3 bonds. In subsequent three component reactions of 1 with N,N‐dicyclohexylcarbodiimide (CyN=C=NCy) and pyridine, different addition patterns led to completely different products. Addition of CyN=C=NCy first and then pyridine into complex 1 resulted in the formation of (BODDIiPr)Lu2(CH2SiMe3)[CyNC(NCy)CHC(NCy)NCy(SiMe3)][CyNC(C6H4N)NCy] (4) with insertion of two molecules of CyN=C=NCy into the Lu‐µ2‐CHSiMe3 bond. Reversing the addition sequence generated (BODDIiPr)Lu2[CyNC(NCy)C6H4N][CyNC(=CHSiMe3)NCy)][CyNC(C6H4N)NCy] (5) with insertion of only one molecule of CyN=C=NCy into the Lu‐µ2‐CHSiMe3 bond. The possible mechanistic pathway to generate 4 was elucidated by DFT calculations. [ABSTRACT FROM AUTHOR]