Sodium hydride → 2-Methoxycarbonyl-1-triisopropylsilylpyrrole

HRID 1108263Notes

Reaction equation

HRID 1108263 reaction equation
I[C:2]1[CH:6]=[C:5]([C:7]([O:9][CH3:10])=[O:8])[N:4]([Si:11]([CH:18]([CH3:20])[CH3:19])([CH:15]([CH3:17])[CH3:16])[CH:12]([CH3:14])[CH3:13])[CH:3]=1.[H-].[Na+].N1C=CC=C1C(OC)=O.C([Si](Cl)(C(C)C)C(C)C)(C)C>CCCCC.O1CCCC1>[CH3:10][O:9][C:7]([C:5]1[N:4]([Si:11]([CH:12]([CH3:14])[CH3:13])([CH:18]([CH3:20])[CH3:19])[CH:15]([CH3:17])[CH3:16])[CH:3]=[CH:2][CH:6]=1)=[O:8]

Participants

7

Reactant 4

HCID 24758Sodium hydrideHCID 136930Methyl pyrrole-2-carboxylateHCID 139400Triisopropylsilyl chlorideHCID 187846613-Iodo-5-methoxycarbonyl-1-triisopropylsilylpyrrole

Product 1

HCID 187846382-Methoxycarbonyl-1-triisopropylsilylpyrroleYield 73%

Reagents, catalysts & solvents 2

HCID 8003PentaneSolventHCID 8028TetrahydrofuranSolvent2×

Procedure

The 3-iodo-5-methoxycarbonyl-1-triisopropylsilylpyrrole starting material can be prepared as follows. Sodium hydride (80% dispersion; 660 mg, 22 mmol) was washed with pentane and suspended in tetrahydrofuran (20 mL). A solution of methyl pyrrole-2-carboxylate (1.251 g, 10 mmol) in tetrahydrofuran (10 mL) was added and the mixture stirred at room temperature. When gas evolution ceased, triisopropylsilyl chloride (1.928 mg, 10 mmol) was added dropwise, and the mixture was stirred for 1 hour, heated at reflux overnight, and partitioned between ether and water. The ethereal layer was dried (magnesium sulfate) and concentrated in vacuo. The residue was purified by chromatography using hexanes:ethyl acetate (8:1) to yield 2-methoxycarbonyl-1-triisopropylsilylpyrrole as an oil (2.05 g, 73%): 1H NMR (CDCl3) δ 7.12 (m, 2H), 6.26 (m, 1H), 3.78 (m, 3H), 1.76 (sept, 3H, J=7.6 Hz), 1.04 (d, 18 H, J=7.6 Hz).

Workup

  1. stirringthe mixture was stirred for 1 hour
  2. temperatureheated
  3. temperatureat reflux overnight
  4. custompartitioned between ether and water
  5. dry with materialThe ethereal layer was dried (magnesium sulfate)
  6. concentrationconcentrated in vacuo
  7. customThe residue was purified by chromatography

Sources & evidence

ORD record
ord-d16158c41ba7410d90c0876df7218622
Source dataset
uspto-grants-2000_05
Patent number
US06066639

Reaction notes

Loading…