Toluene → 1-(1,3-Dioxolan-2-yl)-2-(1-hydroxy-2,3,4,5-tetramethyl-2-cyclopentenyl)benzene

HRID 15696

Reaction equation

HRID 15696 reaction equation
[O:1]1[CH2:5][CH2:4][O:3][CH:2]1[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][C:7]=1Br.C([Li])CCC.[CH3:18][C:19]1[C:20](=[O:27])[CH:21]([CH3:26])[CH:22]([CH3:25])[C:23]=1[CH3:24].C1(C)C=CC=CC=1>C(OCC)C.CCCCCC.O>[O:1]1[CH2:5][CH2:4][O:3][CH:2]1[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][C:7]=1[C:20]1([OH:27])[CH:21]([CH3:26])[CH:22]([CH3:25])[C:23]([CH3:24])=[C:19]1[CH3:18]

Participants

8

Reactant 4

HCID 1140TolueneHCID 410922,3,4,5-Tetramethyl-2-cyclopentenoneHCID 5535342-(2-Bromophenyl)-1,3-dioxolaneHCID 178418339Butyllithium

Product 1

HCID 230162511-(1,3-Dioxolan-2-yl)-2-(1-hydroxy-2,3,4,5-tetramethyl-2-cyclopentenyl)benzene

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 3283Diethyl EtherSolvent2×HCID 8058HexaneSolvent

Conditions

Temperature
25 °C

Procedure

Under a nitrogen atmosphere, a solution of 2-(1,3-dioxolan-2-yl)-bromobenzene (34.36 g, 150.0 mmol) in diethyl ether (206 g) was cooled to −70° C. and a solution of n-butyllithium in n-hexane (1.56 M, 100.96 mL) was added dropwise thereto. After keeping the temperature for 1 hr, a solution of 2,3,4,5-tetramethylcyclopentenone (21.77 g, 157.5 mmol) in diethyl ether (137 g) was added dropwise to the mixture. After raising the temperature to 25° C., the mixture was stirred for 3 hrs. After quenching the reaction by addition of toluene and water, the aqueous layer was removed. The obtained organic layer was washed with saturated brine and then dried over sodium sulfate. The solvent was removed to give a crude product of 1-(1,3-dioxolan-2-yl)-2-(1-hydroxy-2,3,4,5-tetramethyl-2-cyclopentenyl)benzene. To the obtained crude product were added tetrahydrofuran (770 g), 3% aqueous hydrochloric acid solution (385.2 g) and acetone (77 g) and the mixture was stirred at 25° C. for 24 hrs. After the reaction, toluene was added the reaction mixture. The organic layer was washed with water and saturated brine and then dried over sodium sulfate, and the solvent was removed. The residue was purified by silica gel column chromatography to give 2-(2,3,4,5-tetramethylcyclopentadienyl)benzaldehyde (15.78 g, yield 46.5%).

Workup

  1. customfor 1 hr
  2. customAfter quenching
  3. customthe reaction
  4. customthe aqueous layer was removed
  5. washThe obtained organic layer was washed with saturated brine
  6. dry with materialdried over sodium sulfate
  7. customThe solvent was removed

Sources & evidence

ORD record
ord-f6a49e03fdab405fa43d456223d399f4
Source dataset
uspto-grants-2010_06
Patent number
US07732643B2

Linked notes

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