Lawesson's reagent → tert-butyl (2S,4RS)-4-(3-phenylpropyl)-5-thioxo-2-pyrrolidinecarboxylate

HRID 481246Notes

Reaction equation

HRID 481246 reaction equation
O=[C:2]1[NH:6][C@H:5]([C:7]([O:9][C:10]([CH3:13])([CH3:12])[CH3:11])=[O:8])[CH2:4][C@H:3]1[CH2:14][CH2:15][CH2:16][C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1.COC1C=CC(P2(SP(C3C=CC(OC)=CC=3)(=S)S2)=[S:32])=CC=1>C1C=CC=CC=1>[C:17]1([CH2:16][CH2:15][CH2:14][CH:3]2[C:2](=[S:32])[NH:6][C@H:5]([C:7]([O:9][C:10]([CH3:13])([CH3:12])[CH3:11])=[O:8])[CH2:4]2)[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1

Participants

4

Reactant 2

HCID 87949Lawesson's reagentHCID 86587563tert-butyl (2S,4R)-5-oxo-4-(3-phenylpropyl)-2-pyrrolidinecarboxylate

Product 1

HCID 86587564tert-butyl (2S,4RS)-4-(3-phenylpropyl)-5-thioxo-2-pyrrolidinecarboxylateYield 179.8%

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Procedure

A mixture of pyroglutamate 8c (245.4 mg, 0.809 mmol) and Lawesson's reagent (164 mg, 0.404 mmol) in 6 mL benzene was stirred at reflux for 17 h, then concentrated. The crude product was purified by flash chromatography (0.5 to 1 to 1.5 to 2% MeOH/CHCl3) to afford 232 mg (90%) of the thiolactam 8d as a 2:1 mixture of diastereomers.

Workup

  1. temperatureat reflux for 17 h
  2. concentrationconcentrated
  3. customThe crude product was purified by flash chromatography (0.5 to 1 to 1.5 to 2% MeOH/CHCl3)

Sources & evidence

ORD record
ord-f0757e6051c04cb4b4ab1d61176dad8b
Source dataset
uspto-grants-2003_11
Patent number
US06653295B2

Reaction notes

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