Triethylamine → 4-tert-butoxycarbonyl-4H-furo[3,2-b]pyrrole-5-carboxylic acid methyl ester

HRID 1363301Notes

Reaction equation

HRID 1363301 reaction equation
[O:1]1[C:8]2[CH:7]=[C:6]([C:9]([O:11][CH3:12])=[O:10])[NH:5][C:4]=2[CH:3]=[CH:2]1.C(N(CC)CC)C.[O:20](C(OC(C)(C)C)=O)[C:21]([O:23][C:24]([CH3:27])([CH3:26])[CH3:25])=O.CCOC(C)=O.CCCCCC>C(Cl)Cl.CN(C1C=CN=CC=1)C>[CH3:12][O:11][C:9]([C:6]1[N:5]([C:21]([O:23][C:24]([CH3:27])([CH3:26])[CH3:25])=[O:20])[C:4]2[CH:3]=[CH:2][O:1][C:8]=2[CH:7]=1)=[O:10]

Participants

7

Reactant 4

HCID 8471TriethylamineHCID 90495Di-tert-butyl dicarbonateHCID 5082263methyl 4H-furo[3,2-b]pyrrole-5-carboxylateHCID 21226206Ethyl acetate hexane

Product 1

HCID 596486034-tert-butoxycarbonyl-4H-furo[3,2-b]pyrrole-5-carboxylic acid methyl esterYield 62%

Reagents, catalysts & solvents 2

HCID 142844-(Dimethylamino)pyridineCatalystHCID 6344DichloromethaneSolvent

Procedure

To a solution of methyl 4H-furo[3,2-b]pyrrole-5-carboxylate (1.0 g, 6.06 mmol) in CH2Cl2 (10 ml) was added triethyl amine (1.85 g, 18.2 mmol) and DMAP (148 mg 1.22 mol). Then BOC2O (2.0 g, 9.1 mmol) was added. The resulting mixture was stirred overnight. After the reaction was complete as judged TLC analysis (10% EtOAc/hexane), the reaction mixture was washed with water and brine and dried over Na2SO4. After filtration, the filtrate was concentrated and the crude product was purified by silica gel chromatography (20% EtOAc in hexane) to give 4-tert-butoxycarbonyl-4H-furo[3,2-b]pyrrole-5-carboxylic acid methyl ester as a white solid (987 mg, 62%). 1H NMR (400 MHz, CDCl3) δ (ppm) 7.45 (d, J=1.47 Hz, 1H), 6.82 (s, 1H), 6.59 (s, 1H), 3.80 (s, 3H), 1.55 (s, 9H).

Workup

  1. washthe reaction mixture was washed with water and brine
  2. dry with materialdried over Na2SO4
  3. filtrationAfter filtration
  4. concentrationthe filtrate was concentrated
  5. customthe crude product was purified by silica gel chromatography (20% EtOAc in hexane)

Sources & evidence

ORD record
ord-19c654556d1c4c8e9feb0d3ef25eceef
Source dataset
uspto-grants-2011_02
Patent number
US07884124B2

Reaction notes

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