Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Hydrochloric Acid | HCID 313 | — |
| Reactant | Methyl 2-chloropyridine-4-carboxylate | HCID 2736842 | — |
| Reactant | HCID 178506382 | HCID 178506382 | — |
| Catalyst | HCID 178418397 | HCID 178418397 | — |
| Solvent | Tetrahydrofuran | HCID 8028 | — |
| Product | HCID 66732272 | HCID 66732272 | 92.3% |
Reaction Steps
To a solution of methyl 2-chloroisonicotinate (4.80 g, 28 mmol) and Pd(PPh3)4 (0.647 g, 0.56 mmol) in tetrahydrofuran (50 mL) under nitrogen in a dried flask was added a freshly prepared solution of (4-(trifluoromethoxy)benzyl)zinc(II) bromide (12.56 g, 39.20 mmol) in tetrahydrofuran (90 mL). The resulting bright yellow mixture was heated to 60° C. for 2 h 30 min, then cooled to room temperature. The reaction was quenched by the addition of 10% aqueous NH4Cl. It was diluted with ethyl acetate. After phase separation, the organic layer was washed with brine, dried over MgSO4 and evaporated. The residue was suspended in 50 mL MTBE and sonicated, then the yellow insolubles were filtered off and washed with MTBE. The volume of the filtrate was increased to ca. 150 mL, then 5 mL MeOH was added, followed by hydrogen chloride (4 M in dioxane) (7.00 mL, 28.00 mmol). A colorless precipitate formed, which then dissolved again. The solvents were evaporated. The residue was dissolved in ca. 15 mL DCM and then MTBE and heptanes were added. An oil had formed that was triturated and after a few minutes a solid started to form. It was sonicated and then stirred at room temperature for 20 min. The formed solid was collected and washed with MTBE and dried. The solid was dissolved in DCM and washed with 10% K2CO3. After phase separation, the aqueous layer was extracted with DCM. The combined organic layers were dried over MgSO4 and evaporated. Methyl 2-(4-(trifluoromethoxy)benzyl)isonicotinate (8.04 g, 92%) was isolated as a pale yellow oil. 1H NMR (400 MHz, cdcl3) δ 3.93 (s, 3H), 4.22 (s, 2H), 7.11-7.17 (m, 2H), 7.24-7.31 (m, 2H), 7.67-7.72 (m, 2H), 8.68-8.72 (m, 1H). MS m/z 312 (M+H)+
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US08415378B2 |
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| Source dataset | uspto-grants-2013_04 |
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| ORD ID | ord-c85ce13be79b4bf3a6be0ae0bb3a12ee |
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| Source note | uspto-grants-2013_04 |
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