Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Triethylamine | HCID 8471 | — |
| Reactant | p-Toluenesulfonic acid monohydrate | HCID 521998 | — |
| Reactant | bis(4-methoxyphenyl)chloromethane | HCID 10706646 | — |
| Reactant | 2-[N-(tert-butoxycarbonyl)amino]-3-hydroxy-2-methylpropanoic acid tert-butyl ester | HCID 11119311 | — |
| Solvent | Ethanol | HCID 702 | — |
| Solvent | Diethyl Ether | HCID 3283 | — |
| Product | HCID 11825571 | HCID 11825571 | — |
Reaction Steps
To a solution of the alcohol 9 (100 mg, 0.36 mmol) in 2 mL of diethyl ether was added 1 eq of p-toluenesulfonic acid monohydrate (69 mg) dissolved in 6 mL of EtOH. The reaction mixture was concentrated under reduced pressure at 40° C., and the residue was dissolved in 6 mL of EtOH and concentrated again. This process was repeated 4 times, at which time no starting material was present on TLC analysis. The resulting white solid was suspended in 3 mL of CH2Cl2, and treated with 4.5 eq of triethylamine (0.23 mL) followed by 1 eq of bis(4-methoxyphenyl)chloromethane (95 mg). The reaction mixture was stirred for 1 hour at room temperature. The solution was then partitioned between 10 mL of EtOAc and 10 mL of H2O. The aqueous layer was extracted with 10 mL of EtOAc followed by the usual work up of the combined organic layers. Purification by silica gel column chromatography (20% EtOAc in hexane) provided the amino ester 12a as a colorless oil (107 mg, 73% from 9): 1H NMR (CDCl3) δ 1.17 (3H, s), 1.46 (9H, s), 3.35 (1H, d, J=11.2), 3.44 (1H, d, J=11.2), 3.76 (3H, s), 3.77 (3H, s), 4.82 (1H, s), 6.80-6.84 (4H, m), 7.27-7.31 (4H, m). Anal. (C23H31NO5) C, H, N.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US07989649B2 |
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| Source dataset | uspto-grants-2011_08 |
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| ORD ID | ord-aecf59858b4b42ba89fbf6c5e9bc97f4 |
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| Source note | uspto-grants-2011_08 |
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