Reaction #1134

Reaction equation

pyridine

5-(4-tert-butyldimethylsilyloxyphenyl)-3-(1-methyl-2-pyrrolidinyl)pyridine

cesium fluoride

→

5-(4-hydroxyphenyl)-3-(1-methyl-2-pyrrolidinyl)pyridine

Yield 93.0%

Solvents

methanol

Conditions

Workup

1. 1
   TemperatureThe stirred mixture was heated
2. 2
   Temperatureat reflux for 18 h under inert atmosphere
3. 3
   TemperatureAfter cooling the solvent
4. 4
   Otherwas removed in vacuo
5. 5
   workup.DISSOLUTIONthe resulting oil was dissolved in ethyl acetate (50 mL)
6. 6
   WashThis was washed with water (20 mL), brine (20 mL)
7. 7
   Dryingdried (MgSO4)
8. 8
   Concentrationconcentrated
9. 9
   OtherThe crude material was chromatographed on "flash" silica gel with ethyl acetate:hexane (1:2 ) to 10% methanol

Procedure

The above-described pyridine derivative (750 mg, 2.04 mmol) was dissolved in methanol (40 mL) and cesium fluoride (620 mg, 4.08 mmol) was added. The stirred mixture was heated at reflux for 18 h under inert atmosphere. After cooling the solvent was removed in vacuo and the resulting oil was dissolved in ethyl acetate (50 mL). This was washed with water (20 mL), brine (20 mL), dried (MgSO4) and concentrated. The crude material was chromatographed on "flash" silica gel with ethyl acetate:hexane (1:2 ) to 10% methanol: ethyl acetate as eluant to afford 5-(4-hydroxyphenyl)-3-(1-methyl-2-pyrrolidinyl)pyridine 480 mg, 93% as a colorless foam, 1H NMR (CDCl3, 300 MHz): δ 8.66 (d, J=2 Hz, 1 H), 8.43 (d, J=2 Hz, 1 H), 7.90 (s, 1 H), 7.32 (d, J=9 Hz, 2 H), 6.81 (d, J=9 Hz, 2 H), 3.33 (t, J=8 Hz, 1 H), 3.22 (t, J=8 Hz, 1 H), 2.41 (m, 1 H), 2.28 (s, 3 H), 2.10 (m, 2 H), 1.93 (m, 2 H).

Source