Dibromomethane → {1-Methyl-2-[(1,2,2-trimethylbicyclo[3.1.0]hex-3-yl)methyl]cyclopropyl}methanol

HRID 1978254Notes

Reaction equation

HRID 1978254 reaction equation
BrCBr.[C:4](Br)(=O)C.[CH3:8]/[C:9](=[CH:12]\[CH2:13][CH:14]1[CH2:18][CH:17]=[C:16]([CH3:19])C1(C)C)/[CH2:10][OH:11].[CH3:22][C:23](OC)([CH3:25])[CH3:24]>C(OCC)C.Cl[Ti](Cl)(Cl)Cl.[Zn]>[CH3:8][C:9]1([CH2:10][OH:11])[CH2:12][CH:13]1[CH2:14][CH:18]1[CH2:17][CH:16]2[C:25]([CH3:4])([CH2:19]2)[C:23]1([CH3:22])[CH3:24]

Participants

8

Reactant 4

HCID 3024DibromomethaneHCID 10482Acetyl bromideHCID 15413tert-Butyl methyl etherHCID 6438195(2E)-2-Methyl-4-(2,2,3-trimethyl-3-cyclopenten-1-yl)-2-buten-1-ol

Product 1

HCID 22096564{1-Methyl-2-[(1,2,2-trimethylbicyclo[3.1.0]hex-3-yl)methyl]cyclopropyl}methanolYield 55%

Reagents, catalysts & solvents 3

HCID 23994ZincCatalystHCID 24193Titanium TetrachlorideCatalystHCID 3283Diethyl EtherSolvent2×

Procedure

200 g (1.15 mol) of dibromomethane and 1 ml (0.013 mol) of acetyl bromide were added successively to a suspension of 85 g (1.3 mol) of zinc powder and 12 g (83 mmol) of finely ground cuprous bromide in 250 ml of anhydrous diethyl ether. The reaction mixture was stirred until its color changed from grey to black (˜30 minutes). After addition of 50 g (0.26 mol) of (E)-2-methyl-4-(2,2,3-trimethylcyclopent-3-enyl)but-2-en-1-ol dissolved in 50 ml of the same solvent (Et2O), in 10 minutes (the exothermic reaction triggers a smooth reflux of ether), and 2 drops of TiCl4, stirring at room temperature was continued for further 7 hours. The reaction mixture was then diluted with 300 ml of MTBE, filtered through Celite, the filtrate washed with 200 ml of ice-cold 0.1N HCl and 3×200 ml of brine, dried (MgSO4), concentrated in vacuo and distilled rapidly (0.1 Torr) to give 39 g of a yellowish oil containing 81% of [1-methyl-2-(1,2,2-trimethyl-bicyclo[3.1.0]hex-3-yl-methyl)cyclopropyl]methanol (yield 55%). Further purification by distillation using a 15 cm Vigreux column under 0.08 Torr afforded 27.4 g (48% yield) of olfactorily pure product. GC purity >91%, b.p. 104-105° C./0.08 Torr. More product could be recovered from 4.5 g of rejected (66% pure) fractions.

Workup

  1. customgrey to black (˜30 minutes)
  2. customthe exothermic reaction triggers
  3. stirringstirring at room temperature
  4. filtrationfiltered through Celite
  5. washthe filtrate washed with 200 ml of ice-cold 0.1N HCl and 3×200 ml of brine
  6. dry with materialdried (MgSO4)
  7. concentrationconcentrated in vacuo
  8. distillationdistilled rapidly (0.1 Torr)
  9. customto give 39 g of a yellowish oil

Sources & evidence

ORD record
ord-9eb351c53f48408592aa575aa95f4152
Source dataset
uspto-grants-2001_05
Patent number
US06235943B1

Reaction notes

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