Benzoic Acid → Phenethyl Benzoate

HRID 638692Notes

Reaction equation

HRID 638692 reaction equation
[C:1]([OH:9])(=[O:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[C:10]1([CH2:16][CH2:17]O)[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1>CS(O)(=O)=O.C(OP(OCCCCCCCC(C)C)OCCCCCCCC(C)C)CCCCCCC(C)C>[C:1]([O:9][CH2:17][CH2:16][C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1)(=[O:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

5

Reactant 2

HCID 243Benzoic Acid2×HCID 60542-Phenylethanol

Product 1

HCID 7194Phenethyl BenzoateYield 88.4%

Reagents, catalysts & solvents 2

HCID 6395Methanesulfonic AcidCatalystHCID 117488Triisodecyl phosphiteCatalyst

Conditions

Temperature
140 °C

Procedure

A 2-L, 4-neck round bottom flask, fitted with a thermometer, mechanical stirrer, nitrogen inlet tube and Liebig condenser/receiving flask, was charged with 671.7 g (5.50 mol, 1.00 equiv) of benzoic acid, 806.3 g (6.60 mol, 1.20 equiv) of 2-phenylethyl alcohol, 5.30 g (0.43% w/w, 1.0 mol %) of methanesulfonic acid (MSA) and 1.25 g (0.1% w/w) of triisodecylphosphite (TDP). The system was heated gently with slow stirring (<50 rpm) until the benzoic acid dissolved. The air was removed with three cycles of evacuation/nitrogen fill using a mechanical vacuum pump (50-100 torr). The rate of stirring was increased to ca. 200 rpm, the nitrogen sparge was set at 0.2 scfh, and the reaction mixture was heated to 140° C. After a 1-h hold, the temperature was increased to 150° C, and held for 1 h. The temperature was increased to 160° C. and the nitrogen sparge was increased to 0.5 scfh. After a 1-h hold, the reaction mixture was cooled to room temperature and sampled for analysis. The acid number was 8.1 mg KOH/g (97.3% conversion of benzoic acid, corrected for MSA), the APHA color was 66, and the excess 2-phenylethyl alcohol was 7.9% by GLC. To the reaction mixture at 25° C. was added 213 g of 10% w/w aqueous sodium carbonate solution. The batch was heated to 50° C. and stirred for 15 min. The stirring was stopped and the batch was allowed to settle for 30 min. The bottom aqueous layer was removed from the flask with a pipette, and 2-phenylethyl alcohol was removed by vacuum distillation at 180-190° C. (20 torr) for 1 h with a nitrogen sweep of 0.5 scfh. The reaction mixture was cooled to ca. 70° C. and sampled for analysis. The residual 2-phenylethyl alcohol was 0.17% by GLC, the acid number was 0.10 mg KOH/g, and the APHA color was 95. Treatment with activated carbon and filtration as usual (see Example 1) gave 1100 g (88%) of 2-phenylethyl benzoate. The APHA color was 72, the acid number was 0.11 mg KOH/g, the saponification number was 242 mg KOH/g, the residual sulfur was <10 ppm, and the residual phosphorous was <10 ppm.

Workup

  1. temperatureThe system was heated gently
  2. dissolutiondissolved
  3. customThe air was removed with three cycles of evacuation/nitrogen
  4. temperaturewas increased to ca. 200 rpm
  5. customthe nitrogen sparge
  6. temperatureAfter a 1-h hold, the temperature was increased to 150° C
  7. temperatureThe temperature was increased to 160° C.
  8. customthe nitrogen sparge
  9. temperaturewas increased to 0.5 scfh
  10. temperatureAfter a 1-h hold, the reaction mixture was cooled to room temperature
  11. aliquotsampled for analysis
  12. additionTo the reaction mixture at 25° C. was added 213 g of 10% w/w aqueous sodium carbonate solution
  13. temperatureThe batch was heated to 50° C.
  14. stirringstirred for 15 min
  15. waitto settle for 30 min
  16. customThe bottom aqueous layer was removed from the flask with a pipette, and 2-phenylethyl alcohol
  17. customwas removed by vacuum distillation at 180-190° C. (20 torr) for 1 h with a nitrogen sweep of 0.5 scfh
  18. temperatureThe reaction mixture was cooled to ca. 70° C.
  19. aliquotsampled for analysis
  20. filtrationTreatment with activated carbon and filtration as usual (see Example 1)

Sources & evidence

ORD record
ord-b1f78dbb29d5420eb0b0626dea44d922
Source dataset
uspto-grants-2010_04
Patent number
US07691363B2

Reaction notes

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