Synthesis
General procedure for the synthesis of bis(1-adamantyl)phosphonium chloride from di-1-adamantylphosphine: a solution of Ad2PH (10.5 g, 34.7 mmol) and 1,5-diazabicyclo[5.4.0]undec-5-ene (DBU, 6.12 cm3, 40.9 mmol) in toluene (250 cm3) was cooled to -10 °C. The phosgene solution (30.0 cm3, 56.7 mmol) was added slowly through a cannula and transferred through a measuring cylinder. The reaction produced a highly viscous light yellow suspension. To reduce the viscosity and to facilitate stirring, additional toluene (100 cm3) was added through the cannula. The reaction mixture was filtered through a cannula to give a yellow filtrate. The residue was washed with toluene (2 x 100 cm3), the washings were combined with the original filtrate and the volatiles were removed under vacuum to give a light yellow solid. The solid was washed with pentane (2 x 30 cm3, the wash solution was almost colorless), dried under vacuum and separated in a glove box to give a lemon yellow powdery product in 7.84 g yield, 67%.31P NMR chemical shift: δ= 139 ppm, purity 99%, molecular weight (FW) = 336.88.
References
[1] Chemistry - A European Journal, 2003, vol. 9, # 6, p. 1416 - 1425
[2] Organometallics, 2018, vol. 37, # 19, p. 3243 - 3247
[3] Phosphorus, Sulfur and Silicon and the Related Elements, 1995, vol. 102, # 1-4, p. 211 - 216
[4] Patent: US9802185, 2017, B2. Location in patent: Page/Page column 39
[5] Phosphorus, Sulfur and Silicon and the Related Elements, 1994, vol. 88, # 1-4, p. 241 - 244
