Phenylsilane → 1-Methyltetraline

HRID 1756879Notes

Reaction equation

HRID 1756879 reaction equation
C([Li])CCC.C1([SiH3])C=CC=CC=1.[CH3:13][C:14]1[C:23]2[C:18](=[CH:19][CH:20]=[CH:21][CH:22]=2)[CH2:17][CH2:16][CH:15]=1.[H][H]>C1COCC1>[CH3:13][CH:14]1[C:23]2[C:18](=[CH:19][CH:20]=[CH:21][CH:22]=2)[CH2:17][CH2:16][CH2:15]1

Participants

6

Reactant 4

HCID 12752PhenylsilaneHCID 5823271,2-Dihydro-4-methylnaphthaleneHCID 178418339ButyllithiumHCID 178418361HCID 178418361, compound

Product 1

HCID 152621-MethyltetralineYield 70.1%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
0 °C

Procedure

In a dry sealable Schlenk flask under an argon atmosphere 0.059 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 (0.125 mL, 1.58M in hexanes, 0.196 mmol, 1.96 equiv) was added and the mixture was allowed to stir for 10 min. Phenylsilane (0.033 mL, 0.259 mmol, 2.6 equiv) and 0.273 g (1.87 mmol, 19 equiv) 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 2150 psig with hydrogen and placed in an oil bath at 65° C. The reaction mixture was allowed to stir for 184 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 distilled at reduced pressure to yield 0.195 g (1.31 mmol, 70%) of 1-methyl-1,2,3,4-tetrahydronaphthalene with an ee of 70%, determined polarimetrically.

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 65° C
  8. stirringto stir for 184 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. distillationwas distilled at reduced pressure

Sources & evidence

ORD record
ord-a3dd6be67e684c6480617a581967351e
Source dataset
uspto-grants-1995_08
Patent number
US05442119

Reaction notes

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