Acetic Acid → tert-Butyl 1H-pyrrol-1-ylcarbamate

HRID 1511907Notes

Reaction equation

HRID 1511907 reaction equation
[C:1]([O:5][C:6]([CH3:9])([CH3:8])[CH3:7])(=[O:4])[NH:2][NH2:3].CO[CH:12]1[CH2:16][CH2:15][CH:14](OC)O1.C(O)(=O)C>O1CCOCC1>[C:6]([O:5][C:1](=[O:4])[NH:2][N:3]1[CH:12]=[CH:16][CH:15]=[CH:14]1)([CH3:9])([CH3:8])[CH3:7]

Participants

5

Reactant 3

HCID 176Acetic AcidHCID 70091tert-Butyl carbazateHCID 790982,5-Dimethoxytetrahydrofuran

Product 1

HCID 49760548tert-Butyl 1H-pyrrol-1-ylcarbamateYield 12.5%

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent

Procedure

A mixture of tert-butyl carbazate (5.51 g, 41.7 mmol), 2,5-dimethoxytetrahydrofuran (6.5 mL, 50.0 mmol) and acetic acid (33.6 mL) in dioxane (80 mL) was refluxed for 3 h; then cooled, the dark brown reaction mixture was concentrated, the resulting residue was directly silica gel column purified (eluents: 10% EtOAc in hexanes to 50% EtOAc in hexanes) to give the desired product (951 mg) as white solid. 1H NMR (CDCl3, δ in ppm): 7.17 (s, br, 1H), 6.66 (m, 2H), 6.11 (m, 2H), 1.49 (s, 9H).

Workup

  1. temperaturewas refluxed for 3 h
  2. temperaturethen cooled
  3. concentrationthe dark brown reaction mixture was concentrated
  4. custompurified (eluents: 10% EtOAc in hexanes to 50% EtOAc in hexanes)

Sources & evidence

ORD record
ord-ec166998467442ca9d9373a5eb7e3c20
Source dataset
uspto-grants-2012_07
Patent number
US08217043B2

Reaction notes

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