Methanol → HCID 178496862, compound

HRID 1490275Notes

Reaction equation

HRID 1490275 reaction equation
[CH:1]1[C:17]2[C:16]([C:18]([OH:20])=[O:19])=[C:15]3[C:7](=[C:8]4[C:13](=[N:14]3)[CH:12]=[CH:11][CH:10]=[CH:9]4)[NH:6][C:5]=2[CH:4]=[CH:3][CH:2]=1.OS(O)(=O)=O.[CH3:26]O>>[CH:1]1[C:17]2[C:16]([C:18]([O:20][CH3:26])=[O:19])=[C:15]3[C:7](=[C:8]4[C:13](=[N:14]3)[CH:12]=[CH:11][CH:10]=[CH:9]4)[NH:6][C:5]=2[CH:4]=[CH:3][CH:2]=1

Participants

4

Reactant 3

HCID 887MethanolHCID 1118Sulfuric AcidHCID 178524012HCID 178524012, compound

Product 1

HCID 178496862HCID 178496862, compound

Procedure

To a suspension of quindoline-11-carboxylic acid (2.3 g, 8.77 mmol) from Example 1 in MeOH (50 mL) was added concentrated H2SO4 (1.5 ml, 28 mmol). The resulting solution was refluxed for 8 hours, cooled, and partitioned between benzene (100 mL) and water (50 mL). After adjusting the pH to 9 with a saturated solution of K2CO3, the benzene layer was separated, washed with water, dried and concentrated. Purification by LPLC (EtOAc-hexane 1:3) gave 0.28 g of the title compound as greenish-yellow crystals (from hexane), mp 152°-153.5° C. [lit 152.5°-154° C. (Degutis, Y. A.; Ezyarskaite, A. B. Khim. Geterotsik. Soedin. 1986, 1375)]; 1H NMR (CDCl3) δ 9.75 (s, 1H), 9.09 (d, J=6.4, 1H), 8.51 (d, J=8.0, 1H), 8.38 (d, J=7.2, 1H), 7.72-7.62 (m, 3H), 7.49 (d, J=8.0, 1H), 7.38 (t, J=8.0, 1H); 13 C NMR (CDCl3) δ 168.19, 147.81, 144.43, 143.56, 133.91, 130.50, 130.27, 127.40, 126.18, 125.05, 123.66, 122.23, 121.65, 121.06, 111.19, 109.21, 52.54; MS (EI, m/z) 276 (M+) . Acidification of the water layer with HCl gave 1.8 g (78.3%) of recovered starting material.

Workup

  1. temperatureThe resulting solution was refluxed for 8 hours
  2. temperaturecooled
  3. custompartitioned between benzene (100 mL) and water (50 mL)
  4. customthe benzene layer was separated
  5. washwashed with water
  6. customdried
  7. concentrationconcentrated
  8. customPurification by LPLC (EtOAc-hexane 1:3)

Sources & evidence

ORD record
ord-71a2aa546492431d8978a305e8f55339
Source dataset
uspto-grants-1997_10
Patent number
US05681958

Reaction notes

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