Potassium Carbonate → (E)-2-Methoxy-4-styrylpyridine

HRID 930638Notes

Reaction equation

Br[C:2]1[CH:7]=[CH:6][N:5]=[C:4]([O:8][CH3:9])[CH:3]=1.[C:10]1(/[CH:16]=[CH:17]/B(O)O)[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1.C([O-])([O-])=O.[K+].[K+]>CS(C)=O.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.Cl[Pd]Cl.[Fe+2]>[CH3:9][O:8][C:4]1[CH:3]=[C:2](/[CH:17]=[CH:16]/[C:10]2[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=2)[CH:7]=[CH:6][N:5]=1

Participants

Conditions

Temperature: 90 °C

Procedure

4-Bromo-2-methoxypyridine (1.85 g, 9.84 mmol), (E)-phenylvinylboronic acid (4.3 g, 30 mmol), K2CO3 (4.0 g, 30 mmol) and PdCl2(dppf) (400 mg, 0.5 mmol) were stirred in DMSO (15 mL) under vacuum for 30 min. The flask was flushed with nitrogen and the mixture was heated to 90° C. for 30 min. Upon cooling, the mixture was diluted with methylene chloride and washed with 5% lithium chloride solution (5×), dried, concentrated, and the residue was purified by flash column chromatography (silica gel, hexanes/ethyl acetate, 97:3 to 75:25) to provide the title compound (1.93 g, 93%) as an orange oil: 1H NMR (300 MHz, CDCl3) δ 8.12 (d, J=5.2 Hz, 1H), 7.51 (m, 2H), 7.40-7.22 (m, 4H), 7.02-6.94 (m, 2H), 6.78 (s, 1H), 3.95 (s, 3H).

Workup

customThe flask was flushed with nitrogen
temperatureUpon cooling
additionthe mixture was diluted with methylene chloride
washwashed with 5% lithium chloride solution (5×)
customdried
concentrationconcentrated
customthe residue was purified by flash column chromatography (silica gel, hexanes/ethyl acetate, 97:3 to 75:25)

Sources & evidence

ORD record: ord-cb150d341047436d871ce373d236436b
Source dataset: uspto-grants-2016_03
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09296743B2

Reaction notes

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