Toluene → tert-butyl (3R)-4-(5-fluoro-6-methylpyridin-2-yl)-3-methylpiperazine-1-carboxylate

HRID 69127Notes

Reaction equation

Br[C:2]1[N:7]=[C:6]([CH3:8])[C:5]([F:9])=[CH:4][CH:3]=1.[CH3:10][C@H:11]1[NH:16][CH2:15][CH2:14][N:13]([C:17]([O:19][C:20]([CH3:23])([CH3:22])[CH3:21])=[O:18])[CH2:12]1.CC(C)([O-])C.[Na+].C1(C)C=CC=CC=1>C1(P(C2C=CC=CC=2)C2C3OC4C(=CC=CC=4P(C4C=CC=CC=4)C4C=CC=CC=4)C(C)(C)C=3C=CC=2)C=CC=CC=1.O>[F:9][C:5]1[CH:4]=[CH:3][C:2]([N:16]2[CH2:15][CH2:14][N:13]([C:17]([O:19][C:20]([CH3:23])([CH3:22])[CH3:21])=[O:18])[CH2:12][C@H:11]2[CH3:10])=[N:7][C:6]=1[CH3:8]

Participants

Conditions

Temperature: 110 °C

Procedure

To a mixture of 500 mg of 6-bromo-3-fluoro-2-methylpyridine, 580 mg of tert-butyl (3R)-3-methylpiperazine-1-carboxylate, 506 mg of sodium tert-butoxide, and 61 mg of 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene and 7.5 mL of toluene was added 48 mg of tris(dibenzylidenacetone)dipalladium (0), followed by stirring at 110° C. for 3 hours. After cooling to room temperature, the reaction mixture was poured into water and extracted with ethyl acetate. The organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure and the residue was purified by silica gel column chromatography (n-hexane/ethyl acetate) to obtain 780 mg of tert-butyl (3R)-4-(5-fluoro-6-methylpyridin-2-yl)-3-methylpiperazine-1-carboxylate.

Workup

temperatureAfter cooling to room temperature
extractionextracted with ethyl acetate
washThe organic layer was washed with saturated brine
dry with materialdried over anhydrous magnesium sulfate
customThe solvent was evaporated under reduced pressure
customthe residue was purified by silica gel column chromatography (n-hexane/ethyl acetate)

Sources & evidence

ORD record: ord-ea53b8ac4d754d359f1c144f130b2d37
Source dataset: uspto-grants-2014_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08822448B2

Reaction notes

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