Trifluoroacetic acid → HCID 10805772, compound

HRID 1603038Notes

Reaction equation

HRID 1603038 reaction equation
C[O-].[Na+].[C:4]([O:8][C:9]([N:11]1[C:19]2[C:14](=[CH:15][CH:16]=[C:17]([N+:20]([O-:22])=[O:21])[CH:18]=2)[C:13](C(OC)=O)([C:23]([O:25][CH3:26])=[O:24])[CH2:12]1)=[O:10])([CH3:7])([CH3:6])[CH3:5].FC(F)(F)C(O)=O.[N+](=C)([O-])[O-]>CO.C1COCC1.[Na+].[Cl-]>[C:4]([O:8][C:9]([N:11]1[C:19]2[C:14](=[CH:15][CH:16]=[C:17]([N+:20]([O-:22])=[O:21])[CH:18]=2)[CH:13]([C:23]([O:25][CH3:26])=[O:24])[CH2:12]1)=[O:10])([CH3:7])([CH3:6])[CH3:5]

Participants

8

Reactant 4

HCID 6422Trifluoroacetic acidHCID 10691177HCID 10691177, compoundHCID 10942334Sodium MethoxideHCID 178486260Methanenitronate

Product 1

HCID 10805772HCID 10805772, compound

Reagents, catalysts & solvents 3

HCID 887MethanolSolventHCID 5234Sodium ChlorideSolventHCID 8028TetrahydrofuranSolvent

Procedure

NaOMe (4.8 mL of a 1.28 M solution in MeOH, 6.1 mmol) was added dropwise to a solution of 1-(t-butyloxycarbonyl)-3,3-di(methoxycarbonyl)-6-nitroindoline (2.11 g, 5.55 mmol) in THF (100 mL) under nitrogen at 20° C., immediately giving an intense purple colour. After 5 min trifluoroacetic acid (0.51 mL, 6.7 mmol) was added in one portion, causing the nitronate colour to disperse. The pale yellow solution was diluted with aq. NaCl, extracted with EtOAc, and the extracts dried (Na2SO4) and evaporated to give crude title compound as a pale yellow oil. This compound showed signs of air oxidation on standing at room temperature, so was not further purified but used directly in the next step. 1H NMR (CDCl3) δ8.67, 8.34 (2 x br s, 1H, H-7), 7.85 (dd, J=8.2, 2.1 Hz, 1H, H-5), 7.49 (d, J=8.2 Hz, 1H, H-4), 4.48 (dd, J=10.5, 5.4 Hz, 1H, NCH2CH), 4.28 (dd, J=10.5, 5.3 Hz, 1H, NCH2CH), 4.22 (t, J=10.6 Hz, 1H, NCH2CH), 3.82 (s, 3H, CO2Me), 1.60 (s, 9H, t-Bu): 13C NMR δ170.5 (CO2Me), 151.6, 149.1 (C-6,8,9, NCO2, two peaks not observed), 125.5, 117.7, 109.9 (C-4,5,7), (OCMe3 peak not observed), 53.1 (OMe), 50.3 (C-2), 44.4 (C-3), 28.3 (C(CH3)3). HRMS calculated for C15H18N2O6 : 322.11649. Found: 322.11627.

Workup

  1. customimmediately giving an intense purple colour
  2. additionto disperse
  3. extractionextracted with EtOAc
  4. dry with materialthe extracts dried (Na2SO4)
  5. customevaporated

Sources & evidence

ORD record
ord-108eb547872643319e263842e3d1c55b
Source dataset
uspto-grants-1999_11
Patent number
US05985909

Reaction notes

Loading…