Sodium Bicarbonate → Methyl 6-hydroxybenzo[d]oxazole-2-carboxylate

HRID 1878798Notes

Reaction equation

HRID 1878798 reaction equation
Cl.[NH2:2][C:3]1[CH:8]=[CH:7][C:6]([OH:9])=[CH:5][C:4]=1[OH:10].C(=O)([O-])O.[Na+].[CH3:16][O:17][C:18](OC)([O:23]C)[C:19](OC)=O>>[OH:9][C:6]1[CH:7]=[CH:8][C:3]2[N:2]=[C:19]([C:18]([O:17][CH3:16])=[O:23])[O:10][C:4]=2[CH:5]=1

Participants

4

Reactant 3

HCID 516892Sodium BicarbonateHCID 12586559Methyl 2,2,2-trimethoxyacetateHCID 134088224-Aminobenzene-1,3-diol hydrochloride

Product 1

HCID 57951073Methyl 6-hydroxybenzo[d]oxazole-2-carboxylateYield 82%

Conditions

Temperature
100 °C

Procedure

A mixture of 4-aminobenzene-1,3-diol hydrochloride (i in Scheme 1) (0.50 g, 3.1 mmol) and sodium hydrogen carbonate (2.5 mg) in methyl trimethoxyacetate (2 mL) was stirred at 100° C. overnight and then concentrated under reduced pressure. The residue obtained was purified by flash chromatography (silica gel, methylene chloride/ethyl acetate=9/1) to afford methyl 6-hydroxybenzo[d]oxazole-2-carboxylate as a white solid (0.49 g, 82%). 1H-NMR (DMSO-d6, 300 MHz): δ 10.26 (s, 1H), 7.70 (m, 1H), 7.12 (m, 1H), 6.95 (m, 1H), 3.92 (s, 3H) ppm; MS (ESI): 194.3 (M+1).

Workup

  1. concentrationconcentrated under reduced pressure
  2. customThe residue obtained
  3. customwas purified by flash chromatography (silica gel, methylene chloride/ethyl acetate=9/1)

Sources & evidence

ORD record
ord-54751eeac407440d8423d4fe16d1257e
Source dataset
uspto-grants-2012_11
Patent number
US08314107B2

Reaction notes

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