Affiliation:
1. Chair in General and Inorganic Chemistry Saarland University Campus Geb. C4 1 66123 Saarbrücken Germany
2. Inorganic Solid State Chemistry Saarland University Campus Geb. C4 1 66123 Saarbrücken Germany
Abstract
AbstractHeavier tetrylenes attract attention for their potential in synthesis, catalysis and small molecule activation. The coordination byN‐heterocyclic carbenes (NHCs) and cyclic (alkyl)(amino)carbenes (CAACs) results in substantial structural and electronic differences although typically only one of these yields stable derivatives for one and the same tetrylene. We now report both NHC‐ and CAAC‐coordination to a bridged bis(germylene) motif. The NHC‐coordinated bis(germylene) exhibits pyramidal germanium centers with lone pairs of electrons, while with CAAC an unprecedented stable bis(germene) with two Ge=C bonds is isolated. Spectroscopic and crystallographic evidence as well as DFT calculations confirm the effects of σ,π‐conjugation between the two germanium centers in both cases. The coordination of NHC is reversible as the reaction with BPh3liberates the transient bis(germylene) and thus provides an alternative low‐temperature route towards polymers with Ge=Ge bonds.
Funder
Deutsche Forschungsgemeinschaft
Fonds der Chemischen Industrie
Subject
General Chemistry,Catalysis,Organic Chemistry