3-(dimethylamino)-4-fluorophenol

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Sodium cyanoborohydride (0.81 g, 12.7 mmol) is added to a solution of 3-amino-4-fluorophenol (0.66 g, 4.6 mmol), formaldehyde (37% solution, 2.0 g, 24.6 mmol) and acetic acid (0.5 mL) in 20 mL acetonitrile. The reaction is stirred for 2 hour and then poured into 100 mL water. The product is then extracted into diethyl ether (50 mL×3) and the combined organic fractions are washed with brine (40 mL), and dried over anhydrous sodium sulfate. The resulting solution is concentrated in vacuo, and the residue is chromatographed on silica gel using CHCl3:ethyl acetate as eluant (99:1 to 90:10 gradient) to yield 0.72 g (91%) of Compound 22 as a brown solid. 1H-NMR (CDCl3) 6.85 (dd, 1H); 6.40 (m, 1H); 6.27 (m, 1H); 2.84 (s, 6H). 1H-NMR (CDCl3) 133.25 (t, J=9.5 Hz). The product is then extracted into diethyl ether (50 mL×3) the combined organic fractions are washed with brine (40 mL) dried over anhydrous sodium sulfate The resulting solution is concentrated in vacuo the residue is chromatographed on silica gel

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The methyl ether of Example 21 is treated with boron tribromide using general method E to give Compound 22.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The methyl ether of Example 21 is treated with boron tribromide using general method E to give Compound 22.