1-Bromo-3,4-(methylenedioxy)benzene → (2S)-1-(1,3-dioxaindan-5-yl)propan-2-ol

HRID 581388Notes

Reaction equation

HRID 581388 reaction equation
[Mg].Br[C:3]1[CH:11]=[CH:10][C:6]2[O:7][CH2:8][O:9][C:5]=2[CH:4]=1.[CH2:12]1[O:15][C@H:13]1[CH3:14]>O1CCCC1.CCOCC.[Cu]I>[CH3:12][C@H:13]([OH:15])[CH2:14][C:3]1[CH:11]=[CH:10][C:6]2[O:7][CH2:8][O:9][C:5]=2[CH:4]=1

Participants

7

Reactant 3

HCID 758311-Bromo-3,4-(methylenedioxy)benzeneHCID 146262(2S)-2-MethyloxiraneHCID 5462224Magnesium

Product 1

HCID 10986874(2S)-1-(1,3-dioxaindan-5-yl)propan-2-olYield 91%

Reagents, catalysts & solvents 3

HCID 24350Copper(1+) iodide; Copper(I) iodide; Cuprous iodide; Cuprous iodide (CuI)CatalystHCID 3283Diethyl EtherSolventHCID 8028TetrahydrofuranSolvent3×

Conditions

Temperature
-50 °C

Procedure

To a suspension of magnesium turnings (17 g) in 50 mL tetrahydrofuran was added dropwise a solution of 5-bromo-1,3-benzodioxole (93.6 g). After complete addition, the mixture was diluted with 250 mL tetrahydrofuran and the resulting mixture was stirred overnight. 13 mL of the solution (0.78 M) was transferred to a round bottom flask containing copper(I) iodide (0.12 g). The resulting mixture was cooled to -50° C. and a solution of (S)-(-)-propylene oxide in 3 mL tetrahydrofuran was slowly added then stirred 10 min. The mixture was diluted with ether. The isolated organic phase was washed with water and brine. The aqueous wash was extracted with ether (2×) and the combined organic solutions were dried over magnesium sulfate, filtered and concentrated. The residue was purified by silica gel chromatography (50% ether in pentane) to give 1.66 g of the desired product (91%). Chiral HPLC analysis indicated that the optical purity of the material was 98.3%.

Workup

  1. additionAfter complete addition
  2. stirringthen stirred 10 min
  3. washThe isolated organic phase was washed with water and brine
  4. washThe aqueous wash
  5. extractionwas extracted with ether (2×)
  6. dry with materialthe combined organic solutions were dried over magnesium sulfate
  7. filtrationfiltered
  8. concentrationconcentrated
  9. customThe residue was purified by silica gel chromatography (50% ether in pentane)

Sources & evidence

ORD record
ord-d203294884ea452f9a026427ffd9ec78
Source dataset
uspto-grants-1999_07
Patent number
US05919954

Reaction notes

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