Iodine → Lithium diisopropylamide

HRID 25344Notes

Reaction equation

HRID 25344 reaction equation
[Li:1]CCCC.[CH:6]([NH:9][CH:10]([CH3:12])[CH3:11])([CH3:8])[CH3:7].[C:13]1([S:19]([N:22]2[CH:38]=[C:26]3[CH2:27][CH:28]([N:35]([CH3:37])[CH3:36])[C:29]4[CH2:30]C(=O)C=[CH:33][C:24]([C:25]=43)=[CH:23]2)(=[O:21])=[O:20])[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1.[I:39]I.[O:41]1[CH2:45]CCC1>>[Li+:1].[CH3:7][CH:6]([N-:9][CH:10]([CH3:12])[CH3:11])[CH3:8].[C:13]1([S:19]([N:22]2[C:38]([I:39])=[C:26]3[CH2:27][CH:28]([N:35]([CH3:36])[CH3:37])[C:29]4[CH2:30][O:41][CH:45]=[CH:33][C:24]([C:25]=43)=[CH:23]2)(=[O:21])=[O:20])[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1

Participants

7

Procedure

LDA was prepared by addition of n-BuLi (1.56 mol/l hexane solution) 1.08 ml to a solution of diisopropylamine 255 μl in dry tetrahydrofuran 3 ml at −70° C. Then, a solution of compound (20-1) 500 mg in dry tetrahydrofuran 2 ml was added at that temperature to the mixture, which was stirred for 2 h. Then, a solution of iodine 426 mg in dry tetrahydrofuran 2 ml was added and the mixture was stirred for 2 h. Ice was added to the reaction mixtures, which was extracted with chloroform. The extracts were washed with brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue obtained was chromatographed on aluminum oxide in ethyl acetate:hexane (1:5) to give the titled compound as colorless crystals 514 mg. Yield 76%. This was recrystallized from from acetone-isopropyl ether to give colorless crystals, m.p. 136-137° C.

Workup

  1. stirringthe mixture was stirred for 2 h
  2. additionIce was added to the reaction mixtures, which
  3. extractionwas extracted with chloroform
  4. washThe extracts were washed with brine
  5. dry with materialdried over anhydrous magnesium sulfate
  6. concentrationconcentrated under reduced pressure
  7. customThe residue obtained
  8. customwas chromatographed on aluminum oxide in ethyl acetate:hexane (1:5)

Sources & evidence

ORD record
ord-699c1a67994c440bbb3a41c1ddf30073
Source dataset
uspto-grants-2005_02
Patent number
US06858640B2

Reaction notes

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