Silole Silylene Route to NHC‐Stabilized Fused 1‐Silabicycles and 1,1′‐Spirobisiloles

The reaction of an NHC‐stabilized silole silylene (1, 1‐silacyclopentadienylidene) with one equivalent of internal acetylenes resulted in the formation of NHC‐stabilized 1‐silabicyclo[3.2.0]hepta‐1,3,6‐trienes, which subsequently reacted with one equivalent of the acetylene to yield an aryl‐substituted 1,1′‐spirobisilole (SBS). The SBSs can also be prepared by reaction of the NHC‐stabilized silole silylene 1 with two equivalents of the acetylenes in good yields. The electronic structures of these SBSs have been studied by UV/Vis and emission spectroscopy, as well as DFT calculations. Si‐la‐bi‐cy‐cles: Reaction of the NHC‐stabilized silole silylene 1 with internal acetylenes resulted in the formation of NHC‐stabilized 1‐silabicyclo[3.2.0]hepta‐1,3,6‐trienes and 1,1′‐spirobisiloles depending on the reaction conditions and stoichiometry.