Benzene → L-Aspartic acid, 1,4-bis(phenylmethyl) ester, 4-methylbenzenesulfonate (1:1)

HRID 1448026Notes

Reaction equation

HRID 1448026 reaction equation
[NH2:1][C@H:2]([C:7]([OH:9])=[O:8])[CH2:3][C:4]([OH:6])=[O:5].[CH2:10](O)[C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1.O.[C:19]1([CH3:29])[CH:24]=[CH:23][C:22]([S:25]([OH:28])(=[O:27])=[O:26])=[CH:21][CH:20]=1.C1C=CC=CC=1>O>[C:19]1([CH3:29])[CH:20]=[CH:21][C:22]([S:25]([OH:28])(=[O:26])=[O:27])=[CH:23][CH:24]=1.[NH2:1][C@H:2]([C:7]([O:9][CH2:29][C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1)=[O:8])[CH2:3][C:4]([O:6][CH2:10][C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1)=[O:5]

Participants

6

Reactant 4

HCID 241BenzeneHCID 244Benzyl AlcoholHCID 5960L-Aspartic AcidHCID 521998p-Toluenesulfonic acid monohydrate

Product 1

HCID 2808531L-Aspartic acid, 1,4-bis(phenylmethyl) ester, 4-methylbenzenesulfonate (1:1)

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

A stirred mixture of L-aspartic acid (1197 g.; 9.000 moles), benzyl alcohol (5850 g.; 54.00 moles), p-toluenesulfonic acid monohydrate (1746 g.; 9.180 moles), and benzene (3.6 l.) was heated at reflux for 12 hours. The water formed in the reaction (480 ml.) was removed by means of a Dean-Stark trap. The reaction solution was cooled to room temperature then diluted with benzene (3.6 l.) and ether (10.8 l.). The resulting solid was collected on a filter, washed with ether (12.0 l.), and air dried; yield, 3646 g. (83.4%). Recrystallization of this material from methanol (6.0 l.) afforded purified (I); m.p., 158.5°-160.5°; literature m.p., 158°-160°. Four additional esterifications and recrystallizations were carried out on the same scale. The material from the five runs was combined to give 10,310 g. (57.6% recovery) of product suitable for further transformation.

Workup

  1. temperaturewas heated
  2. temperatureat reflux for 12 hours
  3. customwas removed by means of a Dean-Stark trap
  4. additionthen diluted with benzene (3.6 l.) and ether (10.8 l.)
  5. customThe resulting solid was collected on a filter
  6. washwashed with ether (12.0 l.), and air
  7. customdried
  8. customyield
  9. customRecrystallization of this material from methanol (6.0 l.)
  10. customafforded
  11. custompurified (I)
  12. customm.p., 158.5°-160.5°
  13. customliterature m.p., 158°-160°
  14. customFour additional esterifications and recrystallizations
  15. customto give 10,310 g

Sources & evidence

ORD record
ord-d2308b3fedca42bc940a0980c8cd1a3c
Source dataset
uspto-grants-1979_12
Patent number
US04179464

Reaction notes

Loading…