Phosphoric Acid → 4-Ethenylphenyl acetate

HRID 2248955Notes

Reaction equation

HRID 2248955 reaction equation
[CH3:1][CH:2](O)[C:3]1[CH:8]=[CH:7][C:6]([O:9][C:10]([CH3:12])=[O:11])=[CH:5][CH:4]=1.C(OC(=O)C)(=O)C.C1C2NC3C(=CC=CC=3)SC=2C=CC=1.P(=O)(O)(O)O>>[C:10]([O:9][C:6]1[CH:7]=[CH:8][C:3]([CH:2]=[CH2:1])=[CH:4][CH:5]=1)(=[O:11])[CH3:12]

Participants

5

Reactant 4

HCID 1004Phosphoric AcidHCID 7108PhenothiazineHCID 7918Acetic AnhydrideHCID 923454-(1-Hydroxyethyl)phenyl acetate2×

Product 1

HCID 758214-Ethenylphenyl acetate

Procedure

Crude 4'-acetoxyphenylmethylcarbinol (Compound II) [0.58 mol] was mixed with acetic anhydride (0.64 mol), phenothiazine (0.1 wt. %) and 85% by weight phosphoric acid (0.32 mol %). This reaction mixture was fed continuous at a rate of about 2.0 g/minute to the hot reaction vessel, as employed in Examples 1-25, and the product was collected overhead through a distillation column. The reaction vessel was immersed in hot oil maintained at 220°-230° C. and the residue temperature was maintained 180°-190° C. The product (155.4 g) containing Compound I was collected overhead through the distillation column and the residue (24.6 g) was accumulated in the hot reaction vessel. 4-Acetoxystyrene (Compound I) was isolated in 74.1% yield.

Workup

  1. distillationthe product was collected overhead through a distillation column
  2. temperaturemaintained at 220°-230° C.
  3. temperaturethe residue temperature was maintained 180°-190° C
  4. additionThe product (155.4 g) containing Compound I
  5. distillationwas collected overhead through the distillation column

Sources & evidence

ORD record
ord-18f332acd47c46b49b94c3e4a9dda042
Source dataset
uspto-grants-1991_08
Patent number
US05041614

Reaction notes

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