1,2-Dibromoethane → Z,E-1,4-Bis-(4-carbo-tert.-butoxy-styryl)benzene

HRID 974216Notes

Reaction equation

HRID 974216 reaction equation
BrCCBr.[Li+].[Br-].[C:7]([C:14]1[CH:19]=[CH:18][C:17]([C:20]#[C:21][C:22]2[CH:27]=[CH:26][C:25](/[CH:28]=[CH:29]/[C:30]3[CH:35]=[CH:34][C:33]([C:36]([O:38][C:39]([CH3:42])([CH3:41])[CH3:40])=[O:37])=[CH:32][CH:31]=3)=[CH:24][CH:23]=2)=[CH:16][CH:15]=1)([O:9][C:10]([CH3:13])([CH3:12])[CH3:11])=[O:8]>C(O)(C)(C)C.C1COCC1.[Zn]>[C:36]([C:33]1[CH:34]=[CH:35][C:30](/[CH:29]=[CH:28]/[C:25]2[CH:26]=[CH:27][C:22](/[CH:21]=[CH:20]\[C:17]3[CH:16]=[CH:15][C:14]([C:7]([O:9][C:10]([CH3:13])([CH3:12])[CH3:11])=[O:8])=[CH:19][CH:18]=3)=[CH:23][CH:24]=2)=[CH:31][CH:32]=1)([O:38][C:39]([CH3:42])([CH3:41])[CH3:40])=[O:37]

Participants

7

Reactant 3

HCID 78391,2-DibromoethaneHCID 82050Lithium BromideHCID 131717083E-4-(Carbo-tert.-butoxy)-4'-(4-carbo-tert.-butoxystyryl)tolan

Product 1

HCID 67828321Z,E-1,4-Bis-(4-carbo-tert.-butoxy-styryl)benzene

Reagents, catalysts & solvents 3

HCID 23994ZincCatalystHCID 6386tert-ButanolSolvent2×HCID 8028TetrahydrofuranSolvent2×

Procedure

272 g of zinc dust in 270 ml of tert.-butanol are boiled with 24.9 ml of 1,2-dibromoethane until evolution of gas ceases. 55.5 g of CuBr and 66.9 g of LiBr in 200 ml of THF are then carefully added at 50° C. When the exothermic reaction has died down, 272 g of E-4-(carbo-tert.-butoxy)-4'-(4-carbo-tert.-butoxy-styryl)-tolan in 1.7 l of THF and 560 ml of tert.-butanol are added and the reaction mixture is heated under reflux for 4 days. The resulting reaction mixture is then evaporated to dryness, taken up in CH2Cl2 and filtered and the filtrate is washed with dilute HCl, dried and concentrated by evaporation.

Workup

  1. customWhen the exothermic reaction
  2. temperaturethe reaction mixture is heated
  3. temperatureunder reflux for 4 days
  4. customThe resulting reaction mixture
  5. customis then evaporated to dryness
  6. filtrationfiltered
  7. washthe filtrate is washed with dilute HCl
  8. customdried
  9. concentrationconcentrated by evaporation

Sources & evidence

ORD record
ord-ea27f404b8e04b02beac5e2c9faf61f8
Source dataset
uspto-grants-1991_11
Patent number
US05068300

Reaction notes

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