Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Sodium Carbonate | HCID 10340 | — |
| Reactant | (5-Chloro-2-hydroxyphenyl)boronic Acid (contains varying amounts of Anhydride) | HCID 23005362 | — |
| Reactant | HCID 58005640 | HCID 58005640 | — |
| Catalyst | HCID 178418397 | HCID 178418397 | — |
| Solvent | 1,2-Dimethoxyethane | HCID 8071 | — |
| Product | HCID 89555358 | HCID 89555358 | 63% |
Reaction Steps
To a solution of di-tert-butyl (5-bromo-1,2-benzoxazol-3-yl)imidodicarbonate (3.9 g, 9.3 mmol) in dimethoxyethane (100 mL) was added (5-chloro-2-hydroxyphenyl)boronic acid (1.6 g, 9.3 mmol), tetrakis(triphenylphosphine)palladium (1.1 g, 0.9 mmol) and 2 M aqueous sodium carbonate (9.3 mL, 18.6 mmol). The mixture was heated at reflux for 5 h, allowed to cool to ambient temperature and concentrated in vacuo. The residue was diluted with ethyl acetate (75 mL), washed with water (2×40 mL), dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The residue was purified by column chromatography eluting with a 10-50% gradient of ethyl acetate in hexanes to afford di-tert-butyl [5-(5-chloro-2-hydroxyphenyl)-1,2-benzoxazol-3-yl]imidodicarbonate as a colorless solid in 63% yield (2.69 g): 1H NMR (300 MHz, DMSO-d6) δ7.66 (m, 2H), 7.47-7.45 (s, 1H), 7.22-7.19 (m, 3H), 6.90-6.87 (m, 1H), 1.41 (s, 18H); MS (ES+) m/z 460.9 (M+1), 462.9 (M+1).
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US09365578B2 |
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| Source dataset | uspto-grants-2016_06 |
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| ORD ID | ord-e2ac53447ec54051b634162e09878a21 |
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| Source note | uspto-grants-2016_06 |
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