Dicyclohexylamine → N-benzyloxycarbonyl-(L)-pyroglutamic acid chloride

HRID 543247Notes

Reaction equation

HRID 543247 reaction equation
C1(NC2CCCCC2)CCCCC1.[CH2:14]([O:21][C:22]([N:24]1[C:28](=[O:29])[CH2:27][CH2:26][C@H:25]1[C:30]([OH:32])=O)=[O:23])[C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1.S(Cl)([Cl:35])=O>C1(C)C=CC=CC=1>[CH2:14]([O:21][C:22]([N:24]1[C:28](=[O:29])[CH2:27][CH2:26][C@H:25]1[C:30]([Cl:35])=[O:32])=[O:23])[C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1

Participants

5

Reactant 3

HCID 7582DicyclohexylamineHCID 24386Thionyl ChlorideHCID 6376481-(Phenylmethyl) (2S)-5-oxo-1,2-pyrrolidinedicarboxylate

Product 1

HCID 10755299N-benzyloxycarbonyl-(L)-pyroglutamic acid chloride

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Conditions

Temperature
60 °C

Procedure

50 g (0.113 mol) of the previously obtained dicyclohexylamine salt of N-benzyloxycarbonyl-(L)-pyroglutamic acid are mixed to a paste with 1 liter of toluene, 110 ml of thionyl chloride are run in dropwise and the temperature is then raised to 60° C. for 2 hours. The mixture is cooled and filtered, the filtrate is evaporated and the residue is taken up several times with benzene. The acid chloride finally crystallizes from petroleum ether with a practically quantitative yield. Melting point=65°-70° C. (literature=71/72° C.).

Workup

  1. temperatureThe mixture is cooled
  2. filtrationfiltered
  3. customthe filtrate is evaporated
  4. customThe acid chloride finally crystallizes from petroleum ether with a practically quantitative yield
  5. customMelting point=65°-70° C. (literature=71/72° C.)

Sources & evidence

ORD record
ord-f7a66f9272004d0395ab3148a88301b4
Source dataset
uspto-grants-1987_04
Patent number
US04661512

Reaction notes

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