28 / 2023-07-29 12:34:01

Utilization of Ph3P(O): Efficient Transformations via Selective Bond Cleavages with Sodium

triphenylphosphine oxide

New Technologies in Phosphorus Chemistry > 1) New reagents and methods in organophosphorus Chemistry

Triphenylphosphine oxide Ph₃P(O), is a byproduct from the Wittig reactions for producing vitamins in the industry, and is generated tens of thousands of tons each year. A lot of Ph₃P(O) are discarded as waste because of the chemical stability and low added value of the products. We found that by using the resource-abundant and cheap sodium (especially, sodium finely dispersed in paraffin oil with μm-scale sizes, hereafter abbreviated as SD), Ph₃P(O) could be employed as a starting material to efficiently and selectively produce four kinds of organophosphorus intermediates: sodium diphenylphosphinite (2), sodium diphenylphosphide (5), sodium 5H-benzo[b]-phosphindol-5-olate (3) and sodium benzo[b]phos-phindol-5-ide (4) through selective P-C, P-O and C-H bond cleavage. The corresponding organophosphorus compounds were easily obtained by treating these intermediates with electrophiles. In addition, 2 could be facially converted to Ph₂P(O)H which was subsequently transformed to acylphosphine oxides Ph₂P(O)C(O)R or chlorophosphine Ph₂PCl by adjusting the reaction conditions.