Methylenetriphenylphosphine Property

Melting point:

96 °C

Boiling point:

430.0±28.0 °C(Predicted)

Density 

1.10±0.1 g/cm3(Predicted)

solubility 

sol ether, THF, DME, benzene, toluene, DMSO; water and protic solvents destroy the reagent completely

form 

yellow crystals turning white in air

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H302Harmful if swallowed

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P301+P312IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell.

P302+P352IF ON SKIN: wash with plenty of soap and water.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

Methylenetriphenylphosphine Chemical Properties,Usage,Production

Uses

Methylenetriphenylphosphine is used as a methylenating agent for aldehydes and ketones; can convert lactols into hydroxy alkenes; can form a lithio derivative; can be transformed into a β-ketophosphorus ylide.

Preparation

Methylenetriphenylphosphine is usually prepared by treatment of a suspension of Methyltriphenylphosphonium Bromide (or iodide) in an appropriate solvent with a strong base. Butyllithium, dimsylsodium, t-BuOK, and sodamide are commonly used. Typically, a suspension of dry methyltriphenylphosphonium bromide in dry ether or THF is treated with n-Butyllithium at 0°C under N2 and the resulting solution is stirred at rt for 1 h. A yellow to deep orange color indicates the ylide formation. The dimsylsodium (Sodium Methylsulfinylmethylide) procedure requires heating a suspension of NaH in dry DMSO at 75-80 °C for 1 h followed by ice-cooling prior to the addition of phosphonium bromide. A salt-free ylide is usually prepared using Sodium Amide in liquid ammonia or in refluxing THF.

Synthesis Reference(s)

Journal of the American Chemical Society, 106, p. 4547, 1984 DOI: 10.1021/ja00328a041

storage

Methylenetriphenylphosphine should always be handled under N2 or Ar. The ylide should be used as prepared for best results.