The Quest for Stable Silaaldehydes: Synthesis and Reactivity of a Masked Silacarbonyl

The first donor–acceptor complex of a silaaldehyde, with the general formula (NHC)(Ar)Si(H)OGaCl 3 (NHC=N‐heterocyclic carbene), was synthesized using the reaction of silyliumylidene–NHC complex [(NHC) 2 (Ar)Si]Cl with water in the presence of GaCl 3 . Conversion of this complex to the corresponding silacarboxylate dimer [(NHC)(Ar)SiO 2 GaCl 2 ] 2 , free silaacetal ArSi(H)(OR) 2 , silaacyl chloride (NHC)(Ar)Si(Cl)OGaCl 3 , and phosphasilene–NHC...