Cesium carbonate → 2-Methyl-5-vinylpyrimidine

HRID 2176090Notes

Reaction equation

HRID 2176090 reaction equation
[CH:1]([B-](F)(F)F)=[CH2:2].[K+].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C(=O)([O-])[O-].[Cs+].[Cs+].[CH3:33][C:34]1[N:39]=[CH:38][C:37](Br)=[CH:36][N:35]=1>O1CCCC1.O.O.[Pd](Cl)Cl>[CH3:33][C:34]1[N:39]=[CH:38][C:37]([CH:1]=[CH2:2])=[CH:36][N:35]=1

Participants

8

Reactant 4

HCID 10796Cesium carbonateHCID 11776TriphenylphosphineHCID 143877445-Bromo-2-methylpyrimidineHCID 23679353Potassium vinyltrifluoroborate

Product 1

HCID 668483512-Methyl-5-vinylpyrimidine

Reagents, catalysts & solvents 3

HCID 24290Palladium ChlorideCatalystHCID 962WaterSolventHCID 21881883Oxolane--water (1/1)Solvent

Procedure

A solution of potassium vinyltrifluoroborate (666 mg, 4.97 mmol; Aldrich), palladium(II) chloride (18 mg, 0.099 mmol; Aldrich), triphenylphosphine (78 mg, 0.298 mmol; Aldrich), cesium carbonate (4.86 g, 14.91 mmol; Aldrich), and 2-methyl-5-bromopyrimidine (867 mg, 4.97 mmol; AniChem) in tetrahydrofuran/H2O (9:1; 10 mL) was heated at 85° C. under a nitrogen atmosphere for 24 hours. The reaction mixture was cooled to room temperature, diluted with water (15 mL), and extracted with dichloromethane (2×25 mL). The combined organic extracts were dried over MgSO4, filtered, concentrated, and the crude material was purified by flash chromatography (silica gel, 5-60% ethyl acetate in hexanes) to afford the title compound: 1H NMR (300 MHz, CDCl3) δ ppm 2.73 (s, 3H), 5.44 (d, J=11.10 Hz, 1H), 5.86 (d, J=17.85 Hz, 1H), 6.63 (dd, J=17.85, 11.10 Hz, 1H), 8.66 (s, 2H); MS (DCI/NH3) m/z 121 (M+H)+, 138 (M+NH4)+.

Workup

  1. extractionextracted with dichloromethane (2×25 mL)
  2. dry with materialThe combined organic extracts were dried over MgSO4
  3. filtrationfiltered
  4. concentrationconcentrated
  5. customthe crude material was purified by flash chromatography (silica gel, 5-60% ethyl acetate in hexanes)

Sources & evidence

ORD record
ord-356c903cd1b24455aa1ddfadfe996739
Source dataset
uspto-grants-2015_06
Patent number
US09063126B2

Reaction notes

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