4,4-Bis(diethylphosphonomethyl)biphenyl

4,4-Bis(diethylphosphonomethyl)biphenyl is a white powder used as an organic synthesis intermediate for the synthesis of fluorescent brighteners CBS-X, CBS-127, etc.

A mixture of 4,4’-bis(bromoethyl)biphenyl (0.204 g, 0.592 mmol) and P(OEt)3 (1 mL, 6.27mmol) was heated at 150°C for 12 h under N2. The mixture was purified over silica gel column chromatography using ethyl acetate as eluant, giving 258 mg of 4,4-Bis(diethylphosphonomethyl)biphenyl. Yield: 96 percent.