1,1-Dibromoethane → HCID 21709880, compound

HRID 650885Notes

Reaction equation

HRID 650885 reaction equation
[CH:1]1([Si:7]([CH3:19])([CH3:18])[O:8][C:9]2[CH2:10][C:11]3[C:16]([CH:17]=2)=[CH:15][CH:14]=[CH:13][CH:12]=3)[CH2:6][CH2:5][CH2:4][CH2:3][CH2:2]1.[Li][CH2:21][CH2:22][CH2:23][CH3:24].Br[CH:26](Br)[CH3:27]>C1COCC1>[CH:1]1([Si:7]([CH3:19])([CH3:18])[O:8][C:9]2[CH:10]([CH:23]([CH:22]3[C:21]4[C:16](=[CH:15][CH:14]=[CH:13][CH:12]=4)[CH:17]=[C:9]3[O:8][Si:7]([CH3:1])([CH3:18])[CH:26]3[CH2:27][CH2:2][CH2:3][CH2:4][CH2:5]3)[CH3:24])[C:11]3[C:16]([CH:17]=2)=[CH:15][CH:14]=[CH:13][CH:12]=3)[CH2:2][CH2:3][CH2:4][CH2:5][CH2:6]1

Participants

5

Reactant 3

HCID 112011,1-DibromoethaneHCID 21709889HCID 21709889, compoundHCID 178418339Butyllithium

Product 1

HCID 21709880HCID 21709880, compoundYield 28.2%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

To an ice-cooled solution of 2-(cyclohexyldimethylsiloxy)indene (13.62 g, 50.0 mmol) in THF (50 mL) was added dropwise n-BuLi (20.0 mL of a 2.5 M solution in hexanes, 50.0 mmol) and the reaction mixture was stirred overnight at room temperature. The resulting solution was then cooled to −80° C. and treated dropwise with a solution of dibromoethane (4.70 g, 25.0 mmol) in THF (30 mL). The reaction mixture was gradually warmed to room temperature, stirred overnight and washed with saturated ammonium chloride solution (150 mL). The organic phase was dried over sodium sulfate. Solvents were evaporated and the remaining oil was dissolved in Et2O (100 mL). Repeated crystallizations gave a total yield 4.03 g (28.2%) of the title compound as off-white crystals. The first crystalline fraction was used for spectral characterization. EIMS (calcd/found): m/e 570.3349/570.3342. 1H NMR (CDCl3, δ): 7.19-7.07 (m, 6H); 6.99 (td, 3J=7.3 Hz, 4J=1.3 Hz, 2H), 5.65 (s, 2H); 3.17 (m, 2H); 1.84-1.79 (m, AA′, 2H); 1.73 (m, 10H); 1.59-1.54 (m, BB′, 2H); 1.20 (m, 10H); 0.84 (m, 2H); 0.22 (s, 6H); 0.22 (s, 6H). 13C NMR (CDCl3, δ): 164.98; 144.47; 140.65; 126.51; 122.52; 122.33; 118.72; 104.64; 49.09; 27.72; 26.80; 26.48; 26.37; 24.29; −3.60.

Workup

  1. temperatureThe resulting solution was then cooled to −80° C.
  2. temperatureThe reaction mixture was gradually warmed to room temperature
  3. stirringstirred overnight
  4. washwashed with saturated ammonium chloride solution (150 mL)
  5. dry with materialThe organic phase was dried over sodium sulfate
  6. customSolvents were evaporated
  7. dissolutionthe remaining oil was dissolved in Et2O (100 mL)
  8. customcrystallizations

Sources & evidence

ORD record
ord-e766b9fada294439ad232c48f9e0a882
Source dataset
uspto-grants-2001_08
Patent number
US06277778B1

Reaction notes

Loading…