Potassium Carbonate → HCID 19810842, compound

HRID 373673Notes

Reaction equation

HRID 373673 reaction equation
[C:1](=[O:6])([O:4][CH3:5])[O:2][CH3:3].[OH:7][CH2:8][CH2:9][N:10]1[CH2:15][CH2:14][N:13]([CH2:16][CH2:17][OH:18])[CH2:12][CH2:11]1.C(=O)([O-])[O-].[K+].[K+].COC(=O)O.OCCN1CCN(CCO)CC1>>[CH3:3][O:2][C:1](=[O:6])[O:4][CH3:5].[OH:18][CH2:17][CH2:16][N:13]1[CH2:14][CH2:15][N:10]([CH2:9][CH2:8][OH:7])[CH2:11][CH2:12]1

Participants

5

Reactant 4

HCID 11430Potassium CarbonateHCID 12021Dimethyl CarbonateHCID 671511,4-PiperazinediethanolHCID 67621651HCID 67621651, compound

Product 1

HCID 19810842HCID 19810842, compound

Procedure

A total of 180.0 grams (2.0 moles) of dimethyl carbonate, 17.4 grams (0.1 mole) of 1,4-bis(2-hydroxyethyl)piperazine, and 1.0 gram (0.007 mole) of potassium carbonate were combined in a 250 milliliter round bottom flask equipped with a straight distillation head and a magnetic stirrer. The flask contents were heated to reflux under a nitrogen atmosphere. Initial reaction temperatures at reflux were 80° C. at the head and 88° C. in the kettle. A methanol/dimethyl carbonate azeotrope was removed overhead over a period of 7.5 hours. After this time, the flask contents were cooled and the kettle contents were analyzed by capillary gas chromatography (FlD) using a DB-1701 column. The 1,4-bis(2-hydroxyethyl)piperazine was totally converted to a mixture of 1,4-bis(2-hydroxyethyl)piperazine methyl carbonate and 1,4-bis(2-hydroxyethyl)piperazine dimethyl carbonate. The kettle contents were heated for an additional period of 2.5 hours after which the reaction was stopped. The kettle contents were concentrated in vacuo at 20 mm Hg and a temperature of 60° C. using a rotary evaporator. A total of 26.6 grams of material which was about 88 percent pure in 1,4-bis(2-hydroxyethyl)piperazine dimethyl carbonate was obtained. The major by-products were 1,4-bis(2-hydroxyethyl)piperazine methyl carbonate (ca. 1.5 percent) and di-[1,4-bis(2-hydroxyethyl)piperazine]carbonate (ca. 9.9 percent).

Workup

  1. customequipped with a straight distillation head and a magnetic stirrer
  2. temperatureThe flask contents were heated
  3. temperatureto reflux under a nitrogen atmosphere
  4. customInitial reaction temperatures
  5. temperatureat reflux
  6. customwere 80° C. at the head and 88° C. in the kettle
  7. customA methanol/dimethyl carbonate azeotrope was removed overhead over a period of 7.5 hours
  8. temperatureAfter this time, the flask contents were cooled
  9. additionThe 1,4-bis(2-hydroxyethyl)piperazine was totally converted to a mixture of 1,4-bis(2-hydroxyethyl)piperazine methyl carbonate and 1,4-bis(2-hydroxyethyl)piperazine dimethyl carbonate
  10. temperatureThe kettle contents were heated for an additional period of 2.5 hours after which the reaction
  11. concentrationThe kettle contents were concentrated in vacuo at 20 mm Hg
  12. customa temperature of 60° C.
  13. customa rotary evaporator
  14. customwas obtained

Sources & evidence

ORD record
ord-8304481f335748a8af53dc25603be280
Source dataset
uspto-grants-1992_11
Patent number
US05164497

Reaction notes

Loading…