From an Isolable Acyclic Phosphinosilylene Adduct to Donor‐Stabilized SiE Compounds (E=O, S, Se)

Reaction of the arylchlorosilylene‐NHC adduct ArSi(NHC)Cl [Ar=2,6‐Trip 2 C 6 H 3 ; NHC=(MeC) 2 (NMe) 2 C:] 1 with one molar equiv of lithium diphenylphosphanide affords the first stable NHC‐stabilized acyclic phosphinosilylene adduct 2 (ArSi(NHC)PPh 2 ), which could be structurally characterized. Compound 2 , when reacted with one molar equiv selenium and sulfur, affords the silanechalcogenones 4 a and 4 b (ArSi(NHC)(E)PPh 2 , 4 a : E=Se, 4 b : E=S), respectively. Conversion of 2 with an excess of Se and S, through additional insertion of one chalcogen atom into the SiP bond, leads to 3 a and 3 b (ArSi(NHC)(E)‐E‐P(E)Ph 2 , 3 a : E=Se, 3 b : E=S), respectively. Additionally, the exposure of 2 to N 2 O or CO 2 yielded the isolable NHC‐stabilized silanone 4 c , Ar(NHC)(Ph 2 P)SiO.