Sulfuric Acid → Ethyl 5,5-diphenyl-2-isoxazoline-3-carboxylate

HRID 520740Notes

Reaction equation

HRID 520740 reaction equation
C1CC1.[CH2:4]([O:6][C:7]([CH:9]1[CH2:11][C:10]1([C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1)[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1)=[O:8])[CH3:5].OS(O)(=O)=O.[N:29]([O-])=[O:30].[Na+]>CC(O)=O.O>[CH2:4]([O:6][C:7]([C:9]1[CH2:11][C:10]([C:18]2[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=2)([C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)[O:30][N:29]=1)=[O:8])[CH3:5]

Participants

7

Reactant 4

HCID 1118Sulfuric AcidHCID 6351CyclopropaneHCID 11300104HCID 11300104, compoundHCID 23668193Sodium Nitrite

Product 1

HCID 6451155Ethyl 5,5-diphenyl-2-isoxazoline-3-carboxylateYield 97%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 962WaterSolvent

Conditions

Temperature
18 °C

Procedure

The cyclopropane derivative, 2,2-diphenylcyclopropanyl carboxylate ethyl ester (1.0 g, 3.8 mmol) was dissolved in 4.0 mL AcOH at room temperature (18° C.). Into the solution was carefully added 2.0 mL concentrated H2SO4, followed by adding NaNO2 (0.29 g, 4.1 mmol, 1.1 eq) in several portions so that the reaction temperature did not excess 40° C. After addition, the reactants were stirred at room temperature (about 18° C.) for half an hour before the reactants were poured into iced water and extracted with diethyl ether (2×20 mL), the ethereal solutions were combined and washed with sat. NaHCO3 (2×20 mL), then water (20 mL) and brine (20 mL). The washed ethereal solution was then dried over Na2SO4. After removing the desiccant, the ethereal solution was concentrated to furnish a thick oily product. The 1H NMR of the crude product showed that the reaction was clean and the yield was virtually 100%. The thick oily crude product was stirred with 10 mL petrol to give a pale yellow solid 1.07 g, 97% yield.

Workup

  1. customdid not excess 40° C
  2. additionAfter addition
  3. extractionextracted with diethyl ether (2×20 mL)
  4. washwashed with sat. NaHCO3 (2×20 mL)
  5. dry with materialThe washed ethereal solution was then dried over Na2SO4
  6. customAfter removing the desiccant
  7. concentrationthe ethereal solution was concentrated
  8. customto furnish a thick oily product

Sources & evidence

ORD record
ord-253698a3d095466595e86cd3bbade6b3
Source dataset
uspto-grants-2016_05
Patent number
US09328074B2

Reaction notes

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