Phenylsilane → 6-Methoxy-1-methyl-1,2,3,4-tetrahydronaphthalene

HRID 1756878Notes

Reaction equation

HRID 1756878 reaction equation
C([Li])CCC.C1([SiH3])C=CC=CC=1.[CH3:13][O:14][C:15]1[CH:16]=[C:17]2[C:22](=[CH:23][CH:24]=1)[C:21]([CH3:25])=[CH:20][CH2:19][CH2:18]2.[H][H]>C1COCC1>[CH3:13][O:14][C:15]1[CH:16]=[C:17]2[C:22](=[CH:23][CH:24]=1)[CH:21]([CH3:25])[CH2:20][CH2:19][CH2:18]2

Participants

6

Reactant 4

HCID 12752PhenylsilaneHCID 118299387-methoxy-4-methyl-1,2-dihydronaphthaleneHCID 178418339ButyllithiumHCID 178418361HCID 178418361, compound

Product 1

HCID 133961206-Methoxy-1-methyl-1,2,3,4-tetrahydronaphthaleneYield 70.3%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
0 °C

Procedure

In a dry sealable Schlenk flask under an argon atmosphere 0.0592 g (0.099 mmol) (S,S)-ethylene-1,2-bis(η5 -4,5,6,7-tetrahydro- 1-indenyl)titanium (S)-1,1'-binaphth-2,2'-diolate was dissolved in THF (10 mL). The vessel was degassed by exposure to vacuum (2 x ~10 sec), put under an atmosphere of hydrogen and subsequently cooled to 0° C. in an ice water bath. After equilibration, a solution of n-butyllithium (0.122 mL, 1.58M in hexanes, 0.193 mmol, 1.95 equiv) was added and the mixture was allowed to stir for 10 min. Phenylsilane (0.03 1 mL, 0.243 mmol, 2.5 equiv) and 0.378 g (2.19 mmol, 22 equiv ) 6-methoxy-1-methyl-3,4-dihydronaphthalene were then added. The flask was sealed and the solution moved into a dry box and transferred to a Parr® high pressure reaction vessel containing a magnetic stir bar. The pressure vessel was sealed and moved to a fume hood where it was charged to 1800 psig with hydrogen and placed in an oil bath at 68° C. The reaction mixture was allowed to stir for 132 h. The vessel was cooled to room temperature, vented and opened to air. The reaction mixture was worked up by partitioning between diethyl ether hexane (1/4) and water and separating the layers. The organic extract was concentrated and chromatographed on 50 mL silica gel to yield 0.268 g (1.54 mmol, 70%) of 6-methoxy-1-methyl-1,2,3,4-tetrahydronaphthalene with an ee of 94.7%.

Workup

  1. customThe vessel was degassed by exposure to vacuum (2 x ~10 sec)
  2. customThe flask was sealed
  3. customthe solution moved into a dry box
  4. customtransferred to a Parr® high pressure reaction vessel
  5. additioncontaining a magnetic stir bar
  6. customThe pressure vessel was sealed
  7. customplaced in an oil bath at 68° C
  8. stirringto stir for 132 h
  9. temperatureThe vessel was cooled to room temperature
  10. customby partitioning between diethyl ether hexane (1/4) and water
  11. customseparating the layers
  12. extractionThe organic extract
  13. concentrationwas concentrated
  14. customchromatographed on 50 mL silica gel

Sources & evidence

ORD record
ord-08ec1ed559da43c7977c961cc71823f4
Source dataset
uspto-grants-1995_08
Patent number
US05442119

Reaction notes

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