Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Carbon Dioxide | HCID 280 | — |
| Reactant | Pentane | HCID 8003 | — |
| Reactant | Dimethyl oxalate | HCID 11120 | — |
| Reactant | 7-Bromo-1-ethyl-1H-indole | HCID 21950032 | — |
| Reactant | HCID 178418306 | HCID 178418306 | — |
| Solvent | Tetrahydrofuran | HCID 8028 | — |
| Solvent | Ethyl Acetate | HCID 8857 | — |
| Product | HCID 69642170 | HCID 69642170 | 83% |
Reaction Steps
A solution of 1-ethyl-7-bromoindole (2.1 g, 9.4 mmol) in THF (50 mL) was cooled to −78° C. and a 1.7 M solution of tBuLi in pentane (13.8 mL, 23.5 mmol) was added dropwise over 10 min. After 15 min, the resultant brown solution was transferred over 30 min via a cannula cooled with dry ice to a solution of dimethyl oxalate (3.88 g, 32.9 mmol) in THF (40 mL) maintained at −78° C. After 15 min, the mixture was allowed to warm to room temperature and stirred 4 h. The brown solution was treated with pH 7.0 buffer, poured into EtOAc and the EtOAc washed with pH 7.0 buffer, saturated aq NaHCO3, brine, dried (MgSO4) and concentrated to a brown oil. Flash chromatography (20% EtOAc/hexanes) afforded the title compound (1.8 g, 83%) as a yellow oil, which was used without further purification. 1H NMR (400 MHz, DMSO-d6) 7.9 (d, J=8, 1H), 7.55 (m, 2H), 7.2 (dd, J=8, 8 Hz, 1H), 6.66 (d, J=3 Hz, 1H), 4.25 (q, J=7 Hz, 2H), 3.94 (t, J=7 Hz, 3H). MS (electrospray, m/z) 232 (M++1).
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US07109229B2 |
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| Source dataset | uspto-grants-2006_09 |
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| ORD ID | ord-bb6a3e983b29493a8c0c1d3781ebebd4 |
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| Source note | uspto-grants-2006_09 |
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