4-Bromoanisole → Bis(4-methoxyphenyl)phenylphosphine oxide

Participants

Reaction Conditions

Reaction Steps

A slurry of magnesium (133.7 g, 5.50 mol), tetrahydrofuran (988 g), and 1,2-dibromoethane (0.1 g, 0.5 mmol) was refluxed for 20 min. under a blanket of nitrogen. 4-Bromoanisole (1002 g, 5.357 mol) was added by drop over 6 h at a rate to maintain 70° C. The reaction mixture was heated for an additional hour. Dichlorophenylphosphine oxide (479.4 g, 2.459 mol) was added by drop to maintain a temperature of 35° C. over 5 h. The reaction mixture was worked up to give bis(4-methoxyphenyl)phenylphosphine oxide (770.8 g, 93% yield) as a viscous amber oil. 31P NMR: (d6-DMSO) δ 30.2 (s).

Provenance & Evidence