N-methyl-2-pyrrolidone → 2,4,8,10-tetrakis(tert-butyl)-6-chloro-12H-dibenzo[d,g][1,3,2]dioxaphosphocin

Participants

Reaction Steps

To a solution of 25.0 g (0.059 mol) of 2,2'-methylenebis(4,6-di-tert-butylphenol) and 0.57 mL (5.9 mmol) of 1-methyl-2-pyrrolidinone in 275 mL of toluene at ambient temperature is added dropwise 5.16 mL (0.059 mol) of phosphorus trichloride. After the addition is complete, the reaction mixture is refluxed for eight hours. After cooling the mixture to ambient temperature, the toluene is removed in vacuo and the reaction mass is recrystallized twice from 250 mL of 98% acetonitrile and 2% toluene (% by volume) in acetonitrile. The recrystallization solvent is removed by decantation and the residue is dried under vacuum to give 21.4 g (79% yield) of the title compound as an off-white solid melting at 227°-230° C.

Provenance & Evidence