Sodium Hydroxide → 4-Methyl-1-(triphenyl-lambda5-phosphanylidene)-pentan-2-one

Participants

Reaction Steps

111.6 g of isobutylcarbonylmethyltriphenylphosphonium bromide in 1500 ml of methylene chloride is mixed with 1500 ml of 2N NaOH and stirred for 30 minutes at room temperature. The organic phase is separated, washed with water and dried on sodium sulfate. After filtration and evaporation of the solvent, the residue is recrystallized in tert-butyl methyl ether. 72.2 g of title compound 1, with a melting point of 120°-121° C., is obtained. By variations of the ketone component in reaction step a), other phosphoranes of the formula can be produced analogously. ##STR9## II. (5E,7E,22E)-(1S,3R)-1,3-bis-(tert-butyl-dimethyl silyloxy-9,10-seco-24a-homo-5,7,10(19)-22-cholestatetraene-24-one 2

Provenance & Evidence