1,4-Dihydroxy-2,2,6,6-tetramethylpiperidine → 2,4,8,10-Tetra-tert-butyl-6-[1-hydroxy-2,2,6,6-tetramethylpiperidin-4-yloxy]-dibenzo[d,g][1,3,2]dioxaphosphocin

Participants

Reaction Steps

In a flame-dried flask under nitrogen, 4.4 ml of phosphorous trichloride in 100 ml of dry toluene is treated with a solution of 21.27 grams of 2,2'-methylene-bis-(4,6-di-tert-butylphenol) and 13.9 ml of triethylamine in 80 ml of toluene at a temperature not exceeding 5° C. The reaction is stirred at ambient temperature for 12 hours and the suspension is cooled to 5° C. The mixture is treated with 8.61 grams of 4-hydroxy-1-oxyl-2,2,6,6-tetramethylpiperidine and 7 ml of triethylamine in 100 ml of dry toluene. After stirring the mixture at room temperature for 12 hours, the mixture is filtered and the filtrate concentrated under reduced pressure. The residue is crystallized from acetonitrile to give 17.0 grams of a pale red solid.

Provenance & Evidence