Potassium Carbonate → Ethyl 5-bromo-6-methyl-3-pyridinecarboxylate

HRID 1619130Notes

Reaction equation

[Br:1][C:2]1[C:3](Br)=[N:4][CH:5]=[C:6]([CH:12]=1)[C:7]([O:9][CH2:10][CH3:11])=[O:8].[CH3:14]B(O)O.C(=O)([O-])[O-].[K+].[K+]>C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.O1CCOCC1>[Br:1][C:2]1[C:3]([CH3:14])=[N:4][CH:5]=[C:6]([CH:12]=1)[C:7]([O:9][CH2:10][CH3:11])=[O:8]

Participants

Conditions

Temperature: 110 °C

Procedure

An oven-dried resealable Schlenk tube was charged with ethyl 5,6-dibromonicotinate (preparation 47b, 1.09 g, 3.5 mmol), methylboronic acid (0.24 g, 4.0 mmol), potassium carbonate (1.46 g, 10.6 mmol) and 1,4-dioxane (27 mL). The Schlenk tube was subjected to three cycles of evacuation-backfilling with argon, and then tetrakis(triphenylphosphine)palladium(0) (0.41 g, 0.35 mmol) was added. After three new cycles of evacuation-backfilling with argon, the Schlenk tube was sealed and the mixture was stirred and heated in an oil bath to 110° C. After 3 days, the mixture was cooled, filtered through Celite® and the filtrate was evaporated. Purification of the residue by flash chromatography (97:3 to 9:1 hexanes/ethyl acetate) gave the title compound (0.41 g, 45%) as a solid.

Workup

customAfter three new cycles of evacuation-backfilling with argon, the Schlenk tube was sealed
temperaturethe mixture was cooled
filtrationfiltered through Celite®
customthe filtrate was evaporated
customPurification of the residue by flash chromatography (97:3 to 9:1 hexanes/ethyl acetate)

Sources & evidence

ORD record: ord-991b4010ead64893a379c05a1df52bcc
Source dataset: uspto-grants-2014_07
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08772288B2

Reaction notes

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