Triphenylphosphine → (Carbethoxyhexyl)triphenylphosphonium bromide

Participants

Reaction Steps

To a solution of ethyl 7-bromoheptanoate (10.0 g, 42.17 mmol) in toluene (280 mL) was added solid triphenylphosphine (11.06 g, 42.17 mmol). The solution was refluxed over 24 hours under nitrogen atmosphere and then cooled to room temperature. The supernatant was transferred into a different flask and an excess of triphenylphosphine (5.53 g, 21.09 mmol) was added. The solution was refluxed over 3 days and cooled to room temperature without stirring to favor sedimentation. The supernatant again removed by decantation and the resulting colorless oil was dried over high vacuum affording the title compound 176 (18.24 g) in 87% yield. 1H NMR: (300 MHz, CDCl3) δ: 7.96-7.62 (m, 9H), 7.37-7.08 (m, 6H), 4.11-4.00 (m, 2H), 3.86-3.70 (m, 2H), 2.37-2.32 (m, 4H), 2.28-2.19 (m, 2H), 1.72-1.46 (m, 6H), 1.31-1.25 (m, 2H), 1.22-1.15 (m, 3H). MS (ESI)=419 (Phosphonium Ion).

Provenance & Evidence