Chemical Properties
white to light beige crystalline powder
Uses
(Acetylmethylene)triphenylphosphorane is used as a Wittig reagent in synthetic chemistry, especially for the synthesis of functionalized pyrrolidines and cyclobutanones. It plays as a vital role in asymmetric allylboration for enantioselective synthesis of (+)-awajanomycin.It is also employed as a reactant in the preparation of 1,2-dioxanes with antitrypanosomal activity. Further, it is used in the preparation of amphibian pyrrolizidine alkaloids through allylic aminations and silicon-containing acyclic dienone musk odorants. In addition to this, it is involved in Domino Suzuki/Heck coupling reactions to prepare fluorenylidenes.
Synthesis
The preparative method of (Acetylmethylene)triphenylphosphorane: treatment of Triphenylphosphine with chloro- or Bromoacetone provides the phosphonium salt (eq 1). Deprotonation with a weak base such as bicarbonate in cold water provides the crude ylide which may by isolated by filtration.
storage
Handling, Storage, and Precautions: may be handled in atmosphere for short periods; will decompose in water at pH > 9.
