N,N,N',N'-Tetramethylethylenediamine → 1',2'-Dihydrospiro[cyclopentane-1,3'-indole]-2'-one

HRID 9318

Reaction equation

HRID 9318 reaction equation
[NH:1]1[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[CH2:3][C:2]1=[O:10].[CH2:11]([Li])[CH2:12][CH2:13][CH3:14].CN(C)CCN(C)C.ICCCCI>C1COCC1.O>[NH:1]1[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[C:3]2([CH2:14][CH2:13][CH2:12][CH2:11]2)[C:2]1=[O:10]

Participants

7

Procedure

To a −25° C. solution of oxindole (2.0 g, 15.0 mmol) in 40 (cm3) of anhydrous THF under N2 was added n-butyllithium (1.6 M in hexanes, 19.7 cm3, 31.5 mmol) drop-wise. To the resulting milky solution was added N,N,N′,N′-tetramethylethylenediamine (4.75 cm3, 31.5 mmol). After 30 min. a solution of 1,4-diiodobutane (21.9 g, 70.6 mmol) in THF (3 cm3) was added and the reaction mixture was allowed to warm to RT and stirred for 14 h. The reaction mixture was poured into water, extracted with EtOAc (×2), the combined organic layers were washed with dilute HCl (pH 1) and water (×2), dried (MgSO4) and evaporated. The residue was purified by column chromatography (SiO2, EtOAc:hexane 1:4) to afford the subtitled compound (1.4 g, 7.5 mmol, 50%) as a tan solid: 1H NMR (CDCl3) δ 1.8–2.2 (m, 8H), 6.94 (dd, J=7.5, 1.0 Hz, 1H), 7.01 (dd, J=7.5, 1.0 Hz, 1H), 7.14–7.25 (m, 2H), 9.30 (br s, 1H).

Workup

  1. extractionextracted with EtOAc (×2)
  2. washthe combined organic layers were washed with dilute HCl (pH 1) and water (×2)
  3. dry with materialdried (MgSO4)
  4. customevaporated
  5. customThe residue was purified by column chromatography (SiO2, EtOAc:hexane 1:4)

Sources & evidence

ORD record
ord-70fbe5d426504ba9b0472297ac3af260
Source dataset
uspto-grants-2006_08
Patent number
US07091234B2

Linked notes

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