Cesium carbonate → 1-(5-Bromopyridin-3-yl)-4-methylpiperazine

HRID 1672242Notes

Reaction equation

Br[C:2]1[CH:3]=[N:4][CH:5]=[C:6]([Br:8])[CH:7]=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.C(=O)([O-])[O-].[Cs+].[Cs+].[CH3:57][N:58]1[CH2:63][CH2:62][NH:61][CH2:60][CH2:59]1>O1CCOCC1.CCOC(C)=O.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.C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.[Pd].[Pd]>[Br:8][C:6]1[CH:7]=[C:2]([N:61]2[CH2:62][CH2:63][N:58]([CH3:57])[CH2:59][CH2:60]2)[CH:3]=[N:4][CH:5]=1

Participants

Conditions

Temperature: 150 °C

Procedure

To a suspension of 3,5-dibromopyridine (0.30 g, 4.6 mmol), 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (57 mg, 0.098 mmol), tris(dibenzylideneacetone)dipalladium(0) (32 mg, 0.035 mmol) and cesium carbonate (830 mg, 2.5 mmol) in 1,4-dioxane (4.0 mL) in a sealed r×n vessel was added 1-methylpiperazine (0.170 mL, 1.5 mmol) under argon. The reaction mixture was heated for 30 min in a microwave reactor, at 150° C. The reaction mixture was diluted with EtOAc (50 mL), washed with brine and water, dried over Na2SO4, then filtered and concentrated. The crude reaction product was purified by column chromatography to give 1-(5-bromopyridin-3-yl)-4-methylpiperazine (0.13 g, 39%) as a brown oil. LCMS (FA): Rt=1.03 min, m/z=258.0 (M+H).

Workup

washwashed with brine and water
dry with materialdried over Na2SO4
filtrationfiltered
concentrationconcentrated
customThe crude reaction product
customwas purified by column chromatography

Sources & evidence

ORD record: ord-e7aa9e95f9764b2cb05e7eea5458f25d
Source dataset: uspto-grants-2011_08
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07998952B2

Reaction notes

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