Ethyl Acetate → 1-(2-Fluoroethyl)-4-[3-(methyloxy)-4-nitrophenyl]-1,2,3,6-tetrahydropyridine

HRID 419555Notes

Reaction equation

HRID 419555 reaction equation
[Br-].[F:2][CH2:3][CH2:4][N+:5]1[CH:10]=[CH:9][C:8]([C:11]2[CH:16]=[CH:15][C:14]([N+:17]([O-:19])=[O:18])=[C:13]([O:20][CH3:21])[CH:12]=2)=[CH:7][CH:6]=1.[BH4-].[Na+].CCOC(C)=O>CO>[F:2][CH2:3][CH2:4][N:5]1[CH2:6][CH:7]=[C:8]([C:11]2[CH:16]=[CH:15][C:14]([N+:17]([O-:19])=[O:18])=[C:13]([O:20][CH3:21])[CH:12]=2)[CH2:9][CH2:10]1

Participants

5

Reactant 3

HCID 8857Ethyl AcetateHCID 4311764Sodium borohydrideHCID 666497801-(2-Fluoroethyl)-4-[3-(methyloxy)-4-nitrophenyl]pyridinium bromide

Product 1

HCID 594528351-(2-Fluoroethyl)-4-[3-(methyloxy)-4-nitrophenyl]-1,2,3,6-tetrahydropyridineYield 57.1%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

To 1-(2-fluoroethyl)-4-[3-(methyloxy)-4-nitrophenyl]pyridinium bromide (2.0 g, 5.6 mmol) in MeOH (10 mL) cooled in an ice bath was added NaBH4 (1.1 g, 28 mmol) at such a rate to control the foaming which occurred. The mixture was stirred for 2 h then rotovaped down. EtOAc (200 mL) was added, and the solution was washed with saturated NaHCO3 solution and H2O. The solution was dried (MgSO4), filtered, rotovaped and purified by silica gel chromatography. The desired fractions were combined and rotovaped to give the title compound of step B (0.90 g, 3.2 mmol, 57%) as an oil. 1H NMR (400 MHz, CDCl3) δ 7.86 (d, J=8.4 Hz, 1H), 7.05-7.00 (m, 2H), 6.22-6.18 (m, 1H), 4.73 (dd, J=5.1, 4.8 Hz, 1H), 4.61 (dd, J=5.1, 4.8 Hz, 1H), 3.97 (s, 3H), 3.36-3.31 (m, 2H), 2.94-2.82 (m, 4H), 2.65-2.57 (m, 2H).

Workup

  1. washthe solution was washed with saturated NaHCO3 solution and H2O
  2. dry with materialThe solution was dried (MgSO4)
  3. filtrationfiltered
  4. custompurified by silica gel chromatography

Sources & evidence

ORD record
ord-4ea5f7444a6544d4a9c94b69b31597e5
Source dataset
uspto-grants-2012_01
Patent number
US08093239B2

Reaction notes

Loading…