Toluene → tert-Butyl (S)-2-isopropyl-5-oxopyrrolidine-1-carboxylate

HRID 491905Notes

Reaction equation

HRID 491905 reaction equation
[C:1]([O:5][C:6](=[O:23])[NH:7][C@@H:8]([CH2:12][CH:13]1C(=O)OC(C)(C)[O:15][C:14]1=O)[CH:9]([CH3:11])[CH3:10])([CH3:4])([CH3:3])[CH3:2].C1(C)C=CC=CC=1>CCCCCCC>[C:1]([O:5][C:6]([N:7]1[C:14](=[O:15])[CH2:13][CH2:12][C@H:8]1[CH:9]([CH3:11])[CH3:10])=[O:23])([CH3:4])([CH3:3])[CH3:2]

Participants

4

Reactant 2

HCID 1140TolueneHCID 68890344(S)-[1-(2,2-Dimethyl-4,6-dioxo-[1,3]dioxan-5-ylmethyl)-2-methyl-propyl]-carbamic acid tert-butyl ester

Product 1

HCID 60054970tert-Butyl (S)-2-isopropyl-5-oxopyrrolidine-1-carboxylate

Reagents, catalysts & solvents 1

HCID 8900HeptaneSolvent

Procedure

In a 3 L, one-necked flask (equipped with a magnetic stir bar and a condenser with nitrogen inlet) was charged (S)-[1-(2,2-dimethyl-4,6-dioxo-[1,3]dioxan-5-ylmethyl)-2-methyl-propyl]-carbamic acid, tert-butyl ester prepared in Step B above (147 g, 0.446 mol) and toluene (1.4 L). The reaction mixture was heated to reflux for 4 h then cooled to room temperature and concentrated in vacuo to yield crude product as a residual oil. The crude product was dissolved in heptane (˜200 mL) and loaded onto a Biotage 75 L (800 g silica gel) and eluted with heptanes (1 L), 1:9 (7 L), and 1:3 ethyl acetate-heptane (2 L) to yield the product as an oil.

Workup

  1. customIn a 3 L, one-necked flask (equipped with a magnetic stir bar and a condenser with nitrogen inlet)
  2. temperatureThe reaction mixture was heated
  3. temperatureto reflux for 4 h
  4. concentrationconcentrated in vacuo
  5. customto yield crude product as a residual oil
  6. washeluted with heptanes (1 L), 1:9 (7 L), and 1:3 ethyl acetate-heptane (2 L)

Sources & evidence

ORD record
ord-f879fdbc29c64e268cf4727bbb268491
Source dataset
uspto-grants-2009_05
Patent number
US07531545B2

Reaction notes

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