Sulfuric Acid → HCID 178423839, compound

HRID 1926242Notes

Reaction equation

HRID 1926242 reaction equation
S(=O)(=O)(O)O.CO[CH:8](OC)[C:9]([NH:11][CH2:12][C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][C:14]=1[CH3:19])=[O:10].C([O-])(O)=O.[Na+]>>[CH3:19][C:14]1[CH:15]=[CH:16][CH:17]=[C:18]2[C:13]=1[CH:12]=[N:11][C:9]([OH:10])=[CH:8]2

Participants

4

Reactant 3

HCID 1118Sulfuric AcidHCID 516892Sodium BicarbonateHCID 67520987HCID 67520987, compound

Product 1

HCID 178423839HCID 178423839, compound

Conditions

Temperature
60 °C

Procedure

Concentrated sulfuric acid (18 M; 7.0 mL) was added to 2,2-dimethoxy-N-(2-methylbenzyl)-acetamide (3.04 g, 13.6 mmol) at ambient temperature, and the solution was stirred overnight at ambient temperature and 6 h at 60° C. The cooled reaction mixture was added to ≈50 mL of ice, and the pH of the yellow mixture was adjusted to 7 with NaHCO3 solution. The yellow precipitate was filtered off, washed with water, and dried in vacuo overnight. The yellow solid thus obtained was triturated from EtOH, the mother liquor was concentrated to give a solid, which was triturated against from EtOH. After four such triturations, the mother liquor was adsorbed onto Hydromatrix and chromatographed on silica gel [20 g/70 mL prepacked cartridge, eluting with DCM→2% MeOH in DCM→3% MeOH in DCM→4% MeOH in DCM]. Fractions containing the title compound were combined and dried in vacuo, giving a yellow oil. It was used in the next step without further purification. 1H NMR (400 MHz, DMSO-d6): δ=10.9 (brs, 1H), 8.96 (s, 1H), 7.51 (d, J=8.0 Hz, 1H), 7.42 (dd, J=6.8, 8.0 Hz, 1H), 7.12-6.97 (m, 2H), 6.85 (s, 1H), 2.64 (s, 3H). MS(ES+): m/z=160.06 (100) [MH+]. HPLC: tR=2.27 min (polar—5 min, ZQ3).

Workup

  1. customThe cooled reaction mixture
  2. filtrationThe yellow precipitate was filtered off
  3. washwashed with water
  4. customdried in vacuo overnight
  5. customThe yellow solid thus obtained
  6. customwas triturated from EtOH
  7. concentrationthe mother liquor was concentrated
  8. customto give a solid, which
  9. customwas triturated against from EtOH
  10. customchromatographed on silica gel [20 g/70 mL prepacked cartridge, eluting with DCM→2% MeOH in DCM→3% MeOH in DCM→4% MeOH in DCM]
  11. additionFractions containing the title compound
  12. customdried in vacuo
  13. customgiving a yellow oil
  14. customIt was used in the next step without further purification
  15. customHPLC: tR=2.27 min (polar—5 min, ZQ3)

Sources & evidence

ORD record
ord-c55f648f1b44457e9fce124ebdd9ca3b
Source dataset
uspto-grants-2012_05
Patent number
US08178668B2

Reaction notes

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