Buchwald–Hartwig amination: 2,4-Dichloropyridine → Ethyl 2-[(4-chloro-2-pyridinyl)amino]-1,3-oxazole-5-carboxylate
95% yield, run at 160 °C, as recorded by experimental reaction archive. The written procedure is below.
The atoms, from reactants to products
What was in the flask
| Role | Species | Formula | Yield |
|---|---|---|---|
| Reactant | 2,4-Dichloropyridine | C₅H₃Cl₂N | |
| Reactant | Ethyl 2-amino-1,3-oxazole-5-carboxylate | C₆H₈N₂O₃ | |
| Reagent | Cesium carbonate | CCs₂O₃ | |
| Catalyst | 1,1'-(9,9-Dimethyl-9H-xanthene-4,5-diyl)bis(1,1-diphenylphosphine) | C₃₉H₃₂OP₂ | |
| Catalyst | Bis(dibenzylideneacetone)palladium | C₅₁H₄₂O₃Pd₂ | |
| Solvent | 1,4-Dioxane | C₄H₈O₂ | |
| Product | Ethyl 2-[(4-chloro-2-pyridinyl)amino]-1,3-oxazole-5-carboxylate | C₁₁H₁₀ClN₃O₃ | 95.3% |
Conditions
- Temperature
- 160 °C
Yield
- 95% of Ethyl 2-[(4-chloro-2-pyridinyl)amino]-1,3-oxazole-5-carboxylate.
Procedure
Copied from the source record, unedited
Objective: To make the coupled product on a larger scale for hydrolysis/decarboxylation Pd2(dba)3 (80 mg, 0.09 mmol), 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene (152 mg, 0.26 mmol), 2,4-dichloropyridine (0.378 mL, 3.50 mmol), cesium carbonate (2279 mg, 6.99 mmol) and ethyl 2-aminooxazole-5-carboxylate (546 mg, 3.50 mmol) were added to an oven dried microwave vial and the vial was capped and placed under an inert atmosphere, dioxane (18 mL) was added and the resulting mixture was heated to 160 °C for 1 h by microwave irradiation under a nitrogen atmosphere. The crude product was purified by flash silica chromatography, elution gradient 0 to 3% MeOH (7 N ammonia) in DCM. Pure fractions were evaporated to dryness to afford ethyl 2-(4-chloropyridin-2-ylamino)oxazole-5-carboxylate (892 m
The source
This record comes from experimental reaction archive (ord-5d8d88656735435b992c60c9f2e9cc2e). Open the source and check it against what is on this page.
experimental reaction archive record ord-5d8d88656735435b992c60c9f2e9cc2e from dataset "750 AstraZeneca ELN dataset" (url: https://chemrxiv.org/engage/chemrxiv/article-details/60c9e3f37792a23bfdb2d471). No atom mapping is provided by the source.
How to read this record
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