Buchwald–Hartwig amination: 2,4-Dichloropyridine → Ethyl 2-[(4-chloro-2-pyridinyl)amino]-1,3-oxazole-5-carboxylate
48% yield, run at 100 °C, as recorded by experimental reaction archive. The written procedure is below. One of 5 recorded runs making this product; all of them are compared 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 | 47.86% |
Conditions
- Temperature
- 100 °C
Yield
- 48% of Ethyl 2-[(4-chloro-2-pyridinyl)amino]-1,3-oxazole-5-carboxylate.
Every recorded run making this product
5 runs of this class made the same product and differed in what else was in the flask. They are listed from the highest yield down, with this page's run marked.
| Catalyst | Reagents | Solvent | Temp. | Time | Yield |
|---|---|---|---|---|---|
| 1,1'-(9,9-Dimethyl-9H-xanthene-4,5-diyl)bis(1,1-diphenylphosphine); Bis(dibenzylideneacetone)palladium | Cesium carbonate | 1,4-Dioxane | 100 °C | — | 48% (this run) |
| 1,1'-(9,9-Dimethyl-9H-xanthene-4,5-diyl)bis(1,1-diphenylphosphine); Bis(dibenzylideneacetone)palladium | Potassium Carbonate | Anisole | 90 °C | — | 0% |
| Di-tert-butyl(2',4',6'-tris(propan-2-yl)-(1,1'-biphenyl)-2-yl)phosphane; Bis(dibenzylideneacetone)palladium | Cesium carbonate | 1,4-Dioxane | 160 °C | — | 0% |
| Di-tert-butyl(2',4',6'-triisopropyl-3,6-dimethoxy-(1,1'-biphenyl)-2-yl)phosphine; Bis(dibenzylideneacetone)palladium | Cesium carbonate | 1,4-Dioxane | 160 °C | — | 0% |
| Bis(3,5-bis(trifluoromethyl)phenyl)(3,6-dimethoxy-2',4',6'-tri(propan-2-yl)(1,1'-biphenyl)-2-yl)phosphane; Bis(dibenzylideneacetone)palladium | Cesium carbonate | 1,4-Dioxane | 160 °C | — | 0% |
Procedure
Copied from the source record, unedited
Objective: Comparison of the reactivity of 2-aminooxazole and ester substituted 2-aminooxazole under identical reaction conditions. To an oven-dried round bottomed flask was added ethyl 2-aminooxazole-5-carboxylate (156 mg, 1.00 mmol), cesium carbonate (651 mg, 2.00 mmol), TRIS(DIBENZYLIDENEACETONE)DIPALLADIUM(0) (22.87 mg, 0.02 mmol), (9,9-dimethyl-9H-xanthene-4,5-diyl)bis(diphenylphosphine) (43.4 mg, 0.07 mmol) and 2,4-dichloropyridine (0.108 mL, 1.00 mmol). A reflux condenser was fitted and the vessel was purged with nitrogen. dioxane (2 mL)/DMSO (2 mL) (degassed) was added and the reaction mixture was heated to 100 °C for 16 h. The crude product was purified by ion exchange chromatography, using an SCX column. The desired product was eluted from the column using 7M NH3/MeOH and pure
The source
This record comes from experimental reaction archive (ord-345c2935b6ec4f748049eeb832f405b7). Open the source and check it against what is on this page.
experimental reaction archive record ord-345c2935b6ec4f748049eeb832f405b7 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
This is one experiment, not a rule. It says that on one occasion these species were combined under these conditions and this came out. It does not say the reaction will give the same result on your substrate, and nothing on the page has been generalised into a claim that it would.
The pathway is a separate question, kept on separate pages. A mechanism here is the canonical arrow pushing for a class, run on real structures and labelled rule-derived. It is not evidence, and this record is not a mechanism.
Where to next
More Buchwald–Hartwig amination records
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