Suzuki–Miyaura coupling: 4-bromobenzonitrile + phenylboronic acid → 4-cyanobiphenyl
Ready to scaleCross-couplingC-C
Canonical Pd(0)-catalysed cross-coupling of an aryl halide with an aryl boronic acid. The 4-cyanobiphenyl target is the textbook demonstration substrate — electron-poor aryl halide + electron-rich boronic acid, matched polarity for a clean transmetalation.
Conditions
Pd(PPh3)4 (5 mol%), K2CO3 (2 equiv, heterogeneous solid base), 1,4-dioxane (or dioxane:H2O 4:1 for hydrolytically robust substrates). Reflux 80–90 °C, 4–24 h. Argon or N2 atmosphere.
Workup
Cool, partition between EtOAc + brine, wash organic with sat. NaHCO3 + brine, dry MgSO4, concentrate, recrystallise from EtOH or chromatograph (hexane/EtOAc).
| Compound | Role | Equiv | MW (g/mol) | ρ (g/mL) | Safety |
|---|---|---|---|---|---|
| 4-Bromobenzonitrile623-00-7 · C7H4BrN4-Bromobenzonitrile — electron-poor aryl halide; coupling partner. | reactant | 1.0 | 182.02 | — | Danger |
| Phenylboronic acid98-80-6 · C6H7BO2Phenylboronic acid — electron-rich aryl boronic acid; slight excess to compensate for protodeboronation. | reactant | 1.1 | 121.93 | — | Warning |
| Potassium carbonate584-08-7 · CK2O3 | reagent | 2.0 | 138.21 | — | SDS |
| Tetrakis(triphenylphosphine)palladium14221-01-3 · C72H60P4PdTetrakis(triphenylphosphine)palladium(0) — 5 mol%. Air-stable enough for bench setup but degas anyway. | catalyst5 mol% | 0.05 | 1155.59 | — | WarningSDS |
| 1,4-Dioxane123-91-1 · C4H8O21,4-Dioxane — primary solvent. Often used as 4:1 dioxane/H2O for boronic-acid solubility; the calculator does not split solvent volumes, so adjust by hand if you want the aqueous mix. | solvent | — | 88.11 | 1.030 | DangerSDS |
| (1,1'-Biphenyl)-4-carbonitrile2920-38-9 · C13H9N4-Cyanobiphenyl — pale-yellow crystalline; mp 86–88 °C; recrystallises from EtOH. | product | — | 179.22 | — | Warning |