Dichloromethane → tert-butyl 4-(3-methoxy-4-nitrophenyl)-5,6-dihydropyridine-1(2H)-carboxylate

HRID 871849Notes

Reaction equation

HRID 871849 reaction equation
Br[C:2]1[CH:7]=[CH:6][C:5]([N+:8]([O-:10])=[O:9])=[C:4]([O:11][CH3:12])[CH:3]=1.B1([C:22]2[CH2:27][CH2:26][N:25]([C:28]([O:30][C:31]([CH3:34])([CH3:33])[CH3:32])=[O:29])[CH2:24][CH:23]=2)OC(C)(C)C(C)(C)O1.C(=O)([O-])[O-].[K+].[K+].C(Cl)Cl>CN(C=O)C.C(OCC)(=O)C>[CH3:12][O:11][C:4]1[CH:3]=[C:2]([C:22]2[CH2:27][CH2:26][N:25]([C:28]([O:30][C:31]([CH3:34])([CH3:33])[CH3:32])=[O:29])[CH2:24][CH:23]=2)[CH:7]=[CH:6][C:5]=1[N+:8]([O-:10])=[O:9]

Participants

7

Reactant 4

HCID 6344DichloromethaneHCID 11430Potassium CarbonateHCID 4642098Tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,2,3,6-tetrahydropyridine-1-carboxylateHCID 117464905-Bromo-2-nitroanisole

Product 1

HCID 56945492tert-butyl 4-(3-methoxy-4-nitrophenyl)-5,6-dihydropyridine-1(2H)-carboxylateYield 90%

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideSolventHCID 8857Ethyl AcetateSolvent

Conditions

Temperature
90 °C

Procedure

Argon is bubbled for 10 minutes into a mixture of 4.64 g (20.0 mmol) of the product prepared in step 4.1, 6.25 g (20.2 mmol) of 3,6-dihydro-2H-pyridine-1-N-Boc-4-boronic acid pinacol ester (Frontier Scientific) and 8.29 g (60.0 mmol) of potassium carbonate in 125 mL of anhydrous DMF. 0.98 g (1.2 mmol) of PdCl2dppf.CH2Cl2 is added and the mixture is heated under argon at 90°C. for 3 hours. The resulting mixture is diluted with ethyl acetate and washed twice with water and once with saturated aqueous NaCl. The organic phase is dried over Na2SO4, filtered and concentrated under vacuum. The crude solid obtained is purified by chromatography on a column of silica, eluting with a cyclohexane/ethyl acetate gradient (75/25 to 70/30). 6.02 g of a pale yellow solid are obtained, and are triturated in cyclohexane and then drained by suction and dried in an oven. 5.89 g of the expected product are finally recovered in the form of a white solid. Yield=88%.

Workup

  1. washwashed twice with water and once with saturated aqueous NaCl
  2. dry with materialThe organic phase is dried over Na2SO4
  3. filtrationfiltered
  4. concentrationconcentrated under vacuum
  5. customThe crude solid obtained
  6. customis purified by chromatography on a column of silica
  7. washeluting with a cyclohexane/ethyl acetate gradient (75/25 to 70/30)

Sources & evidence

ORD record
ord-15ed4f1667274f059b946a8f07a3d200
Source dataset
uspto-grants-2015_03
Patent number
US08975250B2

Reaction notes

Loading…