HCID 19899008, compound → HCID 19899077, compound

HRID 1196673Notes

Reaction equation

HRID 1196673 reaction equation
[CH:1]([C:4]1[CH:9]=[CH:8][C:7]([C:10]2[CH:14]3[CH2:15][CH2:16][CH:17]([C:20]([O:22][CH3:23])=[O:21])[CH2:18][CH2:19][CH:13]3[O:12][N:11]=2)=[CH:6][CH:5]=1)([CH3:3])[CH3:2]>C(O)(=O)C.S(=O)(=O)(O)O.[O-2].[O-2].[O-2].[Cr+6]>[CH:1]([C:4]1[CH:5]=[CH:6][C:7]([C:10]2[C:14]3[CH2:15][CH2:16][CH:17]([C:20]([O:22][CH3:23])=[O:21])[CH2:18][CH2:19][C:13]=3[O:12][N:11]=2)=[CH:8][CH:9]=1)([CH3:3])[CH3:2]

Participants

5

Reactant 1

HCID 19899008HCID 19899008, compound

Product 1

HCID 19899077HCID 19899077, compoundYield 43.4%

Reagents, catalysts & solvents 3

HCID 176Acetic AcidCatalystHCID 10219390chromium (VI) trioxideCatalystHCID 1118Sulfuric AcidSolvent

Procedure

1 g (0.003 mol) of methyl 3a,5,6,7,8,8a-hexahydro-3-(4-isopropylphenyl)-4H-cyclohept[d]isoxazole-6-carboxylate (diastereoisomer B) was dissolved in 30 ml of glacial acetic acid containing a few drops of concentrated sulfuric acid. The mixture was stirred and heated at 45° C., whereupon 0.79 g (0.0075 mol) of chromium trioxide was added and the heating was continued for 10 minutes. The acetic acid was removed by evaporation. The mixture was made basic with 2N sodium carbonate solution and extracted with ethyl acetate. Evaporation of the ethyl acetate extract and purification of the residue by column chromatography on silica gel using hexane/ethyl acetate (2:1) for the elution gave 0.408 g of methyl 5,6,7,8-tetrahydro-3-(4-isopropylphenyl)-4H-cyclohept[d]isoxazole-6-carboxylate; NMR: δ CDCl3 : 7.47 (m, 2H), 7.3 (m, 2H), 3.74 (s, 3H), 3.2 (m, 1H), 3.02-2.68 (m, 4H), 2.55 (m, 1 H), 2.3-2.1 (m, 2H), 2.01-1.75 (m, 2H), 1.25 (d, 6H).

Workup

  1. additionwas added
  2. customThe acetic acid was removed by evaporation
  3. extractionextracted with ethyl acetate
  4. customEvaporation of the ethyl acetate
  5. extractionextract
  6. custompurification of the residue by column chromatography on silica gel
  7. washfor the elution

Sources & evidence

ORD record
ord-b35065021756470898e2b3dc5787b3c2
Source dataset
uspto-grants-1992_05
Patent number
US05114960

Reaction notes

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