Hydrogen Bromide → p,p'-(Phenylphosphinylidene)bisphenol

Participants

Reaction Steps

Bis(4-methoxyphenyl)phenylphosphine oxide mixture (2359 g, 6.97 mol), hydrobromic acid (48%, 8344 g, 49.5 mol), and potassium bromide (243 g, 2.04 mol) were stirred at 120° C. for 48 h. The flask was fitted with a sodium sulfite scrubber for containment of methyl bromide. The lower aqueous layer was removed and the product layer was worked up to afford bis(4-hydroxyphenyl)phenylphosphine oxide mixture (Composition VI) as a tan powder (1601 g, 74%). m.p. (DSC): 93° C. 31P NMR (d6-DMSO): δ 27.7 (s, 24.7%); 27.5 (s, 47.7%); 27.4 (s, 25.4%); 27.2 (s, 2.2%).

Provenance & Evidence