Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Triethylamine | HCID 8471 | — |
| Reactant | 1-Hydroxybenzotriazole | HCID 75771 | — |
| Reactant | Tetrahydrofurfurylamine | HCID 253298 | — |
| Reactant | 1,3-Propanediamine, N'-(ethylcarbonimidoyl)-N,N-dimethyl-, monohydrochloride | HCID 2723939 | — |
| Reactant | tert-Butoxycarbonylamino-p-tolyl-acetic acid | HCID 23529223 | — |
| Solvent | Dichloromethane | HCID 6344 | — |
| Solvent | Hexane | HCID 8058 | — |
| Product | HCID 117734966 | HCID 117734966 | 67.3% |
Reaction Steps
A one-necked round-bottom flask was charged with amino(4-methylphenyl)acetic acid (10 g, 60.5 mmol), 1,4-dioxane (300 mL) and 1M NaOH (170 mL). To the resulting solution di-tert-butyl dicarbonate (19.8 g, 90.8 mmol) was added and the solution stirred at room temperature overnight. The dioxane was removed under reduced pressure and the aqueous solution was adjusted to pH 4 with 3M HCl and the product extracted with ethyl acetate (2×50 mL). The combined organic layers were dried over Na2SO4, filtered and the solvent removed under reduced pressure to afford [(tert-butoxycarbonyl)amino](4-methylphenyl)acetic acid as a white solid (15.2 g, y=95%). 1H NMR (DMSO-d6) δ (ppm): 7.44 (d, 1H, J=7.4 Hz), 7.27 (d, 2H, J=7.2 Hz), 7.14 (d, 2H, J=7.3 Hz), 5.03 (d, 1H, J=5.4 Hz), 2.28 (s, 3H), 1.38 (s, 9H). MS (ES1+) m/z: 266.42 (M+1). A one-necked round-bottom flask was charged with [(tert-butoxycarbonyl)amino](4-methylphenyl)acetic acid (16 g, 60.5 mmol), DCM (500 mL) and triethylamine (16.7 mL, 121 mmol). The resulting solution was cooled to 0° C. and N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride (EDC, 13.9 g, 72.6 mmol) and 1-hydroxybenzotriazole (HOBT, 9.8 g, 72.6 mmol) were added. The mixture was stirred for 40 min at 0° C. Then 1-(tetrahydrofuran-2-yl)methanamine (10.6 mL, 103 mmol) was added and the solution stirred at room temperature overnight. After 18 h the reaction was complete (HPLC-MS analysis). The solution was washed with water (2×150 mL), 1M HCl (2×150 mL), and brine (2×150 mL). The organic layers were dried over Na2SO4, filtered and the solvent was removed under reduced pressure to afford a white solid which was taken up in 100 mL of n-hexane and triturated at room temperature for 2 h. The precipitate was filtered and dried under vacuum at 50° C. for 4 h. The solid was dissolved in 100 mL of 1,4-dioxane and 25 mL of 4M HCl solution in dioxane were added. The resulting solution was stirred at room temperature overnight. After solvent removal under vacuum, the residue was taken up in diethyl ether (40 mL) and triturated at room temperature for 2 h. The precipitate was filtered and dried under vacuum at 50° C. to afford Intermediate C as a white solid (11.6 g, y=67% over two steps). 1H NMR (DMSO-d6) δ (ppm): 8.75 (br s, 3H), 7.45 (d, 2H, J=7.5 Hz), 7.22 (d, 2H, J=7.4 Hz), 4.91 (br s, 1H), 3.90-3.51 (m, 4H), 3.22-3.04 (m, 2H), 2.28 (s, 3H), 1.85-1.26 (m, 4H). MS (ES1+) m/z: 249.04 (M+1).
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US09409876B2 |
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| Source dataset | uspto-grants-2016_08 |
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| ORD ID | ord-2feb49a52fae4fffbae16933bda1b9a1 |
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| Source note | uspto-grants-2016_08 |
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