Reaction #7781

Reaction equation

2,4-dimethoxyphenylboronic acid

[4-(1,3-benzoxazol-2-yl)-2-bromophenyl]acetonitrile

triphenylphosphine

potassium carbonate

→

[5-(1,3-benzoxazol-2-yl)-2′,4′-dimethoxy-1,1′-biphenyl-2-yl]acetonitrile

Solvents

DME H2O

Conditions

Workup

1. 1
   TemperatureThe mixture was cooled to rt
2. 2
   Otherthe two layers were separated
3. 3
   Extractionthe aqueous layer was extracted with EtOAc (3×)
4. 4
   Dryingdried over Na2SO4
5. 5
   Otherevaporated to dryness
6. 6
   Otherto give an orange solid
7. 7
   OtherPurification of the crude by flash chromatography on silica gel eluting with a gradient of EtOAc

Procedure

A mixture of 2,4-dimethoxyphenylboronic acid (175 mg, 0.96 mmol), [4-(1,3-benzoxazol-2-yl)-2-bromophenyl]acetonitrile (example 1) (200 mg, 0.64 mmol), dichlorobis(triphenylphosphine)palladium(II) (22 mg, 0.032 mmol), triphenylphosphine (17 mg, 0.064 mmol), and potassium carbonate (177 mg, 1.3 mmol) in degassed DME/H2O (5:1, 12 mL) was heated at 83° C. for 18 h. The mixture was cooled to rt, the two layers were separated and the aqueous layer was extracted with EtOAc (3×). The organics were combined, dried over Na2SO4 and evaporated to dryness to give an orange solid. Purification of the crude by flash chromatography on silica gel eluting with a gradient of EtOAc:hexanes (0 to 40 min: 0 to 20% EtOAc, 40 to 50 min: 50% EtOAc) afforded [5-(1,3-benzoxazol-2-yl)-2′,4′-dimethoxy-1,1′-biphenyl-2-yl]acetonitrile as a yellow solid. 1H NMR (CDCl3, 300 MHz) δ 8.26 (dd, 1H), 8.15 (s, 1H), 7.77 (m, 1H), 7.70 (d, 1H), 7.57 (m, 1H), 7.36 (m, 2H), 7.16 (d, 1H), 6.62 (dd, 1H), 6.57 (s, 1H), 3.88 (s, 3H), 3.78 (s, 3H), 3.64 (q, 2H). MS (ESI) 371 (M+H)+.

Source