Lactic Acid → Hydroxyacetic acid--2-hydroxypropanoic acid (1/1)

HRID 1418667Notes

Reaction equation

HRID 1418667 reaction equation
[C:1]([OH:6])(=[O:5])[CH:2]([CH3:4])[OH:3].[CH2:7]1[O:14]C(=O)C[O:10][C:8]1=[O:9]>>[C:1]([OH:6])(=[O:5])[CH:2]([CH3:4])[OH:3].[C:8]([OH:10])(=[O:9])[CH2:7][OH:14]

Participants

3

Reactant 2

HCID 612Lactic AcidHCID 65432Glycolide

Product 1

HCID 36797Hydroxyacetic acid--2-hydroxypropanoic acid (1/1)

Conditions

Temperature
150 °C

Procedure

The lactide obtained in Example 2 (19 g) and glycolide (1 g) were put into a 100-ml reaction vessel equipped with a stirrer and a nitrogen-introducing tube. After substitution of nitrogen gas was carried out three times, the mixture was stirred at 150° C. for 3 hours in a stream of nitrogen. To the resulting mixture was added 0.4 g of Baylith 5A [synthetic zeolite (Kurita Water Industries Ltd.) ]*2, and the temperature was raised to 195°±5° C. The pressure was reduced gradually to 20 mmHg over 30 minutes, followed by stirring for one hour. After the pressure was reduced gradually to 1 mmHg over 30 minutes, the mixture was stirred at 195°±5° C. for 9 hours to give lactic acid-glycolic acid copolymer in the molten state. The product was cooled to room temperature to give 14.64 g of white copolymer. The weight-average molecular weight of this copolymer was 73,000.

Workup

  1. customequipped with a stirrer
  2. additiona nitrogen-introducing tube
  3. temperaturethe temperature was raised to 195°±5° C
  4. waitThe pressure was reduced gradually to 20 mmHg over 30 minutes
  5. stirringby stirring for one hour
  6. waitAfter the pressure was reduced gradually to 1 mmHg over 30 minutes
  7. stirringthe mixture was stirred at 195°±5° C. for 9 hours

Sources & evidence

ORD record
ord-e76f3879214c4d47aa3bd4a5f9ed90da
Source dataset
uspto-grants-1999_03
Patent number
US05883222

Reaction notes

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