Yield: 64%

Reaction Conditions:

Stage #1: with trimethylaluminum;ammonium chloride in toluene at 20; for 1.5 h;
Stage #2:m-Fluorobenzonitrile in toluene at 85; for 9 h;

Steps:

60.1
4.12 mL (8.24 mmol) of trimethyl aluminum (2.0 M toluene solution) was added to a 10 mL of toluene containing 441 mg (8.24 mmol) of ammonium chloride at room temperature. After stirring for 1.5 hours, 2 g (28.9 mmol) of isobutyronitrile was added EPO thereto and the resulting mixture was heated to 85°C for 9 hours. After completion of a reaction, the reaction solution was poured into 200 mL of chloroform containing 200 g of silicagel and filtered off. The residue was washed with 100 mL of methanol and distillation was conducted to give 731 mg (5.29 mmol) of the title compound in a yield of 64%.[936] NMR: ¹H-NMR(CD OD) δ 7.71~7.44(4H, m)[937] Mass(EI) 139(M⁺+.)

References:

LG LIFE SCIENCES, LTD. WO2006/104356, 2006, A1 Location in patent:Page/Page column 68-69