Diethyl Ether → Tert-butyl 2-(6-chloro-5-methylpyridin-3-yl)acetate

HRID 592150Notes

Reaction equation

HRID 592150 reaction equation
Br[C:2]1[CH:3]=[C:4]([CH3:9])[C:5]([Cl:8])=[N:6][CH:7]=1.[Cl-].[C:11]([O:15][C:16](=[O:19])[CH2:17][Zn+])([CH3:14])([CH3:13])[CH3:12].CCOCC>C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.[Pd].CC(P(C(C)(C)C)[C-]1C=CC=C1)(C)C.C1C=CC([C-]2C(C3C=CC=CC=3)=C(C3C=CC=CC=3)C(C3C=CC=CC=3)=C2C2C=CC=CC=2)=CC=1.[Fe+2].C1COCC1>[Cl:8][C:5]1[N:6]=[CH:7][C:2]([CH2:17][C:16]([O:15][C:11]([CH3:14])([CH3:13])[CH3:12])=[O:19])=[CH:3][C:4]=1[CH3:9]

Participants

7

Reactant 3

HCID 3283Diethyl EtherHCID 2854345-Bromo-2-chloro-3-methylpyridineHCID 178451183HCID 178451183, compound

Product 1

HCID 58447848Tert-butyl 2-(6-chloro-5-methylpyridin-3-yl)acetate

Reagents, catalysts & solvents 3

HCID 6505921(1E,4E)-1,5-diphenylpenta-1,4-dien-3-one; palladiumCatalystHCID 129828017Ditert-butyl(cyclopenta-2,4-dien-1-yl)phosphane;iron(2+);(2,3,4,5-tetraphenylcyclopenta-1,4-dien-1-yl)benzeneCatalystHCID 8028TetrahydrofuranSolvent

Conditions

Temperature
70 °C

Procedure

To a sealed tube was added 5-bromo-2-chloro-3-methylpyridine 86-4 (4.69 g, 22.72 mmol), 0.5 M (2-tert-butoxy-2-oxoethyl) zinc(II) chloride in ether 86-5 (50 mL, 25 mmol), Pd(dba)2 (262 mg, 0.45 mmol), Q-phos (320 mg, 0.45 mmol), and THF (75 mL). The reaction mixture was bubbled with nitrogen for 1 minute and stirred at 70° C. for 4 hours. After cooling to room temperature, all the solvents were evaporated and the residue was redissolved in ethyl acetate, washed with water and brine, dried over Na2SO4 and concentrated to dryness by rotary evaporation. The crude product was purified by silica gel flash chromatography and eluted with 20% ethyl acetate in hexane to give tert-butyl 2-(6-chloro-5-methylpyridin-3-yl)acetate 86-6 as red oil. MS m/z 242.1 (M+1)

Workup

  1. customThe reaction mixture was bubbled with nitrogen for 1 minute
  2. temperatureAfter cooling to room temperature
  3. customall the solvents were evaporated
  4. dissolutionthe residue was redissolved in ethyl acetate
  5. washwashed with water and brine
  6. dry with materialdried over Na2SO4
  7. concentrationconcentrated to dryness by rotary evaporation
  8. customThe crude product was purified by silica gel flash chromatography
  9. washeluted with 20% ethyl acetate in hexane

Sources & evidence

ORD record
ord-12d764d938844d6a9b8a65f121b1755f
Source dataset
uspto-grants-2016_01
Patent number
US09238646B2

Reaction notes

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