10. Sudipta Roy, Birger Dittrich, Totan Mondal, Debasis Koley, A. Claudia Stückl, Brigitte Schwederski, Wolfgang Kaim, Michael John, Suresh Kumar Vasa, Rasmus Linser, and Herbert W. Roesky. Carbene Supported Dimer of Heavier Ketenimine Analogue with P and Si Atoms.Abstract:
A cyclic alkyl(amino) carbene (cAAC) stabilized dimer [(cAAC)Si(P-Tip)]2 (2) (Tip = 2,4,6-triisopropylphenyl) is reported. 2 can be considered as a dimer of the heavier ketenimine (R2C=C=N-R) analogue. The dark-red rod-shaped crystals of 2 were synthesized by reduction of the precursor, cAAC-dichlorosilylene- stabilized phosphinidene (cAAC)SiCl2→P-Tip with sodium napthalenide. The crystals of 2 are storable at room temperature for several months, and stable up to 215 °C under an inert atmosphere. X-ray single-crystal diffraction revealed that 2 contains a cyclic non-planar four-membered SiPSiP ring. Magnetic susceptibility measurements confirmed the singlet spin ground state of 2. Cyclic voltammetry of 2 showed a quasi-reversible one-electron reduction indicating the formation of the corresponding radical anion2·-, which was further characterized by EPR measurements in solution. The electronic structure and bonding of 2 and 2·- were studied by theoretical calculations. The experimentally obtained data are in good agreement with the calculated values.