Iminophosphorane Explained

Iminophosphorane is a kind of organophosphorus compound with the formula . Like the corresponding phosphine oxides and Wittig reagents, iminophosphoranes are ylides. Their bonding is described by two resonance structures.[1]

Preparation

Aza-ylides can be obtained via the reaction of a tertiary phosphine and an organic azide with the loss of dinitrogen. Triphenylphosphine is a commonly used phosphine.

Examples

The parent iminophosphorane has the formula (registry number 25682-80-8) remains only of theoretical interest. Of practical value are derivatives of triorganophosphines and organic amines. A prototype is the phenyl imide derivative of triphenylphosphine, a white, lipophilic solid.

Bis(triphenylphosphine)iminium chloride, a common iminophosphorane, is prepared in two steps from triphenylphosphine :[2]

An iminophosphorane is obtainable from trimethylsilyl azide and triphenylphosphine. Desilylation gives the anion .[3]

Reactions

Iminophosphoranes are one of the components in the aza-Wittig reaction. The other component is an aldehyde or a ketone. They also are components of the Staudinger ligation.[4]

See also

References

  1. 10.1039/D3CS00290J . Reactions of main group compounds with azides forming organic nitrogen-containing species . 2023 . Zhu . Lizhao . Kinjo . Rei . Chemical Society Reviews . 52 . 16 . 5563–5606 . 37519098 .
  2. Book: Ruff. J.K.. Schlientz. W.J. . μ-Nitridobis(triphenylphosphorus)(l+) ("PPN") Salts with Metal Carbonyl Anions . Inorganic Syntheses . Inorganic Synthesis . 15 . 1974 . 84–90 . 10.1002/9780470132463.ch19. 9780470132463.
  3. 10.1016/s0277-5387(00)83838-3 . Phosphorane iminato complexes of transition metals . 1989 . Dehnicke . Kurt . Strähle . Joachim . Polyhedron . 8 . 6 . 707–726 .
  4. 10.1021/acs.chemrev.9b00665 . The Staudinger Ligation . 2020 . Bednarek . Christin . Wehl . Ilona . Jung . Nicole . Schepers . Ute . Bräse . Stefan . Chemical Reviews . 120 . 10 . 4301–4354 . 32356973 .