Diiodomethane → 3-Bromo-5-cyclopropylphenol

Participants

Reaction Conditions

Reaction Steps

To anhydrous CH2Cl2 (10 mL) was added ZnEt2 (12.34 of a 1.0 M in heptane, 12.34 mmol) under nitrogen. The solution was cooled to 0° C., and a solution of trifluoroacetic acid (0.95 mL, 12.34 mmol) in anhydrous CH2Cl2 (4 mL) was added very slowly. After stirring the reaction mixture for 20 m, a solution of CH2I2 (0.99 mL, 12.34 mmol) in CH2Cl2 (4 mL) was added. After an additional 20 m stirring, a solution of the 1-bromo-3-methoxymethoxy-5-vinyl-benzene (1.20 g, 4.94 mmol) in CH2Cl2 (6 mL) was added, and the reaction was allowed to warm to RT. After 1.5 h, the reaction was quenched with saturated aqueous NH4Cl (30 mL) and hexanes (50 mL), and the layers were separated. The aqueous layer was extracted with Et2O (2×40 mL), and the combined organic layers were washed with H2O (30 mL), brine (30 mL), and dried with anhydrous MgSO4. The solvents were evaporated, and the remaining oil was partially purified by flash chromatography on silica gel (0% to 5% EtOAc/hexanes). The partially purified material was placed in i-PrOH (10 mL), and 2 mL of 1.0 M HCl was added. The mixture was aged at 50° C. for 14 h, cooled to RT, and added to H2O (25 mL). The aqueous mixture was extracted with Et2O (3×40 mL), and the combined organics were washed with brine (30 mL), and dried over anhydrous MgSO4. The solvents were evaporated, and the remaining oil was purified by flash chromatography on silica gel (0% to 10% EtOAc/hexanes) to afford 325 mg (31%) of 3-bromo-5-cyclopropyl-phenol (114).

Provenance & Evidence