Acetic Anhydride → (4Z)-4-(4-Cyclopropylbenzylidene)-2-[4-(2-cyclopropylethoxy)phenyl]-1,3-oxazol-5(4H)-one

HRID 1799229Notes

Reaction equation

HRID 1799229 reaction equation
[CH:1]1([CH2:4][CH2:5][O:6][C:7]2[CH:19]=[CH:18][C:10]([C:11]([NH:13][CH2:14][C:15]([OH:17])=[O:16])=O)=[CH:9][CH:8]=2)[CH2:3][CH2:2]1.[CH:20]1([C:23]2[CH:30]=[CH:29][C:26]([CH:27]=O)=[CH:25][CH:24]=2)[CH2:22][CH2:21]1.C([O-])(=O)C.[Na+].C(OC(=O)C)(=O)C>>[CH:20]1([C:23]2[CH:30]=[CH:29][C:26](/[CH:27]=[C:14]3\[N:13]=[C:11]([C:10]4[CH:9]=[CH:8][C:7]([O:6][CH2:5][CH2:4][CH:1]5[CH2:2][CH2:3]5)=[CH:19][CH:18]=4)[O:17][C:15]\3=[O:16])=[CH:25][CH:24]=2)[CH2:22][CH2:21]1

Participants

5

Reactant 4

HCID 7918Acetic AnhydrideHCID 517045Sodium AcetateHCID 115064744-CyclopropylbenzaldehydeHCID 66812105N-[4-(2-Cyclopropylethoxy)benzoyl]glycine

Product 1

HCID 66812352(4Z)-4-(4-Cyclopropylbenzylidene)-2-[4-(2-cyclopropylethoxy)phenyl]-1,3-oxazol-5(4H)-oneYield 75.1%

Conditions

Temperature
120 °C

Procedure

A mixture of N-[4-(2-cyclopropylethoxy)benzoyl]glycine (184 mg, 0.699 mmol) prepared in Example 1 (1b), 4-cyclopropylbenzaldehyde (compound described in Tetrahedron Lett., (2002), 43, 6987-6990, 113 mg, 0.773 mmol), sodium acetate (75 mg, 0.914 mmol), and acetic anhydride (660 μL, 6.99 mmol) was stirred at 120° C. for 30 minutes and then allowed to cool to room temperature. The solidified product was ultrasonically washed with n-hexane (2 mL) and water (4 mL). Then, the precipitate was collected by filtration, washed with water and n-hexane, and dried by heating under reduced pressure to give 196 mg of the title compound (yellow powder, yield 74%). Hereinafter, the compound obtained by this cyclizing reaction is called oxazolone.

Workup

  1. temperatureto cool to room temperature
  2. washThe solidified product was ultrasonically washed with n-hexane (2 mL) and water (4 mL)
  3. filtrationThen, the precipitate was collected by filtration
  4. washwashed with water and n-hexane
  5. customdried
  6. temperatureby heating under reduced pressure

Sources & evidence

ORD record
ord-b91429d560a246449db8ac1f2925e1df
Source dataset
uspto-grants-2013_01
Patent number
US08344029B2

Reaction notes

Loading…