Phenylboronic Acid → (2-Phenyl-3,4,5-trimethoxyphenyl)diphenylphosphine oxide

Participants

Reaction Steps

To a 2 liter Schlenk flask was added (2-iodo-3,4,5-trimethoxyphenyl) diphenylphosphine oxide 21 (30 g, 61 mmol), phenylboronic acid (11.1 g, 91 mmol), and degassed THF (800 ml). A solution of degassed saturated K2CO3 (400 ml) was added afterwards. The whole mixture was degassed with nitrogen for an additional 10 min. Then, Pd(PPh3)4 (1.22 mmol, 1.4 g) was added in the solution through one portion. The mixture was stirred at reflux under nitrogen for 24 hrs. In situ 31PNMR showed that the reaction was complete. The reaction mixture was concentrated under reduced pressure to remove THF and 400 ml of CH2Cl2 was then added. The CH2Cl2 layer was washed with water (200 ml) and brine (200 ml), dried over Na2SO4, and evaporated. The solid residue was recrystallized from EtOAc (100 ml) to give off-white product 22 (23 g). The mother liquid was passed through a silica gel column to give another 4 g of product 22. The total yield was 98%.

Provenance & Evidence