1-Heptanethiol → 2,7-Dibromo-9-(bis-heptylsulfanyl-methylene)fluorene

HRID 393126Notes

Reaction equation

HRID 393126 reaction equation
[H-].[Na+].[CH2:3]([SH:10])[CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH3:9].[Br:11][C:12]1[CH:24]=[CH:23][C:22]2[C:21]3[C:16](=[CH:17][C:18]([Br:25])=[CH:19][CH:20]=3)[C:15](=[C:26](Br)Br)[C:14]=2[CH:13]=1>C(COC)OC.[Ni](Cl)Cl.N1C=CC=CC=1C1C=CC=CN=1.C1(C)C=CC=CC=1>[Br:25][C:18]1[CH:19]=[CH:20][C:21]2[C:22]3[C:14](=[CH:13][C:12]([Br:11])=[CH:24][CH:23]=3)[C:15](=[C:26]([S:10][CH2:3][CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH3:9])[S:10][CH2:3][CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH3:9])[C:16]=2[CH:17]=1

Participants

7

Reactant 3

HCID 154221-HeptanethiolHCID 24758Sodium hydrideHCID 226485382,7-Dibromo-9-(dibromomethylidene)-9H-fluorene

Product 1

HCID 226485432,7-Dibromo-9-(bis-heptylsulfanyl-methylene)fluoreneYield 75%

Reagents, catalysts & solvents 3

HCID 14742,2'-BipyridineCatalystHCID 15773433Dichloronickel;1,2-dimethoxyethaneCatalystHCID 1140TolueneSolvent

Procedure

A 60% dispersion of sodium hydride in mineral oil (3.45 g, 86.25 mmol) was added under a heavy flow of nitrogen to anhydrous toluene (1 L). 1-Heptanethiol (14.65 g, 17.0 mL, 110.7 mmol) was added via syringe. Once effervescence stopped, 2,7-dibromo-9-dibromomethylene-fluorene (2) (18.50 g, 37.46 mmol) was added followed by 2,2′-bipyridyl (0.29 g, 1.87 mmol) and nickel(II) chloride dimethoxyethane adduct (0.41 g, 1.87 mmol). The reaction was stirred overnight at reflux. After cooling to room temperature, the reaction mixture was washed with 2M aqueous sodium hydroxide (2×100 mL), 5% aqueous hydrochloric acid (2×100 mL), water (200 mL), and brine (200 ml) before being dried over sodium sulphate and evaporated to dryness. Excess 1-heptanethiol was removed via Kugelrohr distillation. The crude product was purified by flash chromatography (eluent: petrol 40-60) followed by recrystallisation from iso-hexane to afford 2,7-dibromo-9-(bis-heptylsulfanyl-methylene)-fluorene (3) (16.76 g, 75%) as a bright yellow solid, purity 100% (GC): υmax (KBr, cm−1) 3068, 2949, 2920, 2851, 1588, 1559, 1513, 1443, 1396, 1330; δH(CDCl3, 300 MHz) 9.09 (2H, s), 7.53 (2H, d, 3JHH=6.0 Hz), 7.43 (2H, d, 3JHH=6.0 Hz), 3.04 (4H, t, 3JHH=7.5 Hz) 1.70 (4H, m), 1.43 (4H, m), 1.26 (12H, m), 0.86 (6H, m); δc(CDCl3, 75 MHz) 145.5, 139.7, 137.6, 136.1, 130.3, 129.5, 121.1, 120.3, 36.4, 31.7, 30.1, 28.9, 22.6, 14.1; M+=596 (t).

Workup

  1. temperatureat reflux
  2. washthe reaction mixture was washed with 2M aqueous sodium hydroxide (2×100 mL), 5% aqueous hydrochloric acid (2×100 mL), water (200 mL), and brine (200 ml)
  3. dry with materialbefore being dried over sodium sulphate
  4. customevaporated to dryness
  5. customExcess 1-heptanethiol was removed via Kugelrohr distillation
  6. customThe crude product was purified by flash chromatography (eluent: petrol 40-60)
  7. customfollowed by recrystallisation from iso-hexane

Sources & evidence

ORD record
ord-5ce32c9e0d404cd6986424775c9d44c7
Source dataset
uspto-grants-2004_10
Patent number
US06805922B2

Reaction notes

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