Phenylboronic Acid → 3-Amino-biphenyl-2-carbonitrile

Participants

Reaction Conditions

Reaction Steps

2-Amino-6-bromo-benzonitrile (1.0 Kg, 5.07 moles) and toluene (10 L, 10 vol) were added to a 20 L glass-lined reactor equipped with mechanical stirrer under inert atmosphere. Potassium acetate (996 g, 10.16 moles) and phenylboronic acid (866, 7.10 moles) were added into the solution and the solution was degassed with nitrogen for 30 min. After this time, dichloro-bis(triphenylphosphine) palladium (II) (17.8 g, 0.025 moles) was added to the reaction mixture at ambient temperature. The mixture was heated to 110° C., where it stirred for 17 h. At the conclusion of this period, the reaction progress was monitored by HPLC, which indicated the reaction was completed. The reaction mixture was filtered through a celite bed. The filtrate was transferred back to the reactor and concentrated hydrochloric acid (˜35%, 2 L, 2 vol) was charged to the reactor at ambient temperature. The HCl salt of the title compound precipitated out from the reaction and was collected by filtration. The HCl salt was transferred into the 20 L reactor and then made basic with 10% NaOH solution (pH 8-9). The resulting product was extracted with ethyl acetate (10 L, 10 vol). The ethyl acetate layer was washed with water (5 L, 5 vol) and then the solvent was evaporated under vacuum to give a residue. Hexanes (5 L, 5 vol) were added to the residue at 35-40° C., and the resulting slurry was cooled to ambient temperature. Once at the prescribed temperature, the product was collected by filtration to provide a pale yellow solid (802 g, 81.4%, 99% by HPLC). 1H NMR (DMSO-D6, 400 MHz, δ ppm); 7.43-7.52 (m, 5H), 7.33-7.37 (m, 1H), 6.83 (d, J=8 Hz, 1H), 6.62 (d, J=8 Hz, 1H), 6.1 (s, 2H). ES-MS: [M++1]=194.23.

Provenance & Evidence