Stability of phosphinidenes—Are they synthetically accessible?
Benkő, Zoltán; Streubel, Rainer; Nyulászi, László; BenkÅ Zoltán; Department of Inorganic Chemistry, Budapest University of Technology and Economics; Streubel Rainer; Institute of Inorganic Chemistry, University of Bonn; Nyulászi László; Department of Inorganic Chemistry, Budapest University of Technology and Economics
Журнал:
Dalton Transactions
Дата:
2006
Аннотация:
The relative stability of different singlet phosphinidenes (Râ P) has been investigated by using isodesmic reactions. The energies of these reactions with several R groups were calculated with DFT and ab initio methods at different levels of theory. The best stabilising effect on the phosphinidene centre is exhibited by the Râ ²2C.dbd;N-group, resulting in a singlet ground state. The analysis of the electron density in the parent H2C.dbd;Nâ P, indicates a considerable double bond character of the PN bond. Further tuning of the C.dbd;N Ï -bond polarity is possible by variation of the Râ ² substituents. Using trimethylsilyl substituents or incorporating the carbon atom in a Ï -withdrawing pentafulvene ring the stabilization and the computed singlet triplet separation increases. The thermodynamics and the kinetics of dimerisation reactions of the most stabilised Râ ²2C.dbd;Nâ P indicates that these compounds are likely synthetic targets.
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