Hexane → Zifrosilone

HRID 1938570Notes

Reaction equation

HRID 1938570 reaction equation
[CH3:1][Si:2]([CH3:11])([CH3:10])[C:3]1[CH:4]=[C:5](Br)[CH:6]=[CH:7][CH:8]=1.C([Li])CCC.CCCCCC.C([O:25][C:26](=O)[C:27]([F:30])([F:29])[F:28])C>C(OCC)C.C1CCCCC1.C(OCC)C>[F:28][C:27]([F:30])([F:29])[C:26]([C:5]1[CH:6]=[CH:7][CH:8]=[C:3]([Si:2]([CH3:11])([CH3:10])[CH3:1])[CH:4]=1)=[O:25]

Participants

7

Reactant 4

HCID 8058HexaneHCID 9794Ethyl trifluoroacetateHCID 4167050(3-Bromophenyl)trimethylsilaneHCID 178418339Butyllithium

Product 1

HCID 60811ZifrosiloneYield 53%

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolventHCID 21895417Cyclohexane diethyletherSolvent

Conditions

Temperature
-78 °C

Procedure

To a solution of 3-trimethylsilyl-bromobenzene (7.62 g, 33.3 mmol) in diethyl ether (35 ml) was added at 0° C. 1.5M n-butyllithium in hexane (22.2 ml, 33.3 mmol) over 10 min. Then the mixture was allowed to react 15 min at room temperature, cooled to -78° C. and ethyltrifluoroacetate (14.2 g, 100 mmol) was added over 5 min. Then the mixture was allowed to react 15 min at -78° C., the cooling bath was removed and when the temperature rose to 0° C. 3N HCl (35 ml) was added dropwise. The organic layer was separated, washed with water, brine, dried over MgSO4 and concentrated. Chromatography (silica gel, cyclohexane/diethyl ether: 90/10) followed by distillation under reduced pressure afforded the expected compound as a colorless oil (4.32 g, 53% yield), b.p. 120° C., Rf: 0.28 (cyclohexane/diethyl ether: 95/5).

Workup

  1. customto react 15 min at room temperature
  2. customto react 15 min at -78° C.
  3. customthe cooling bath was removed
  4. customrose to 0° C
  5. addition3N HCl (35 ml) was added dropwise
  6. customThe organic layer was separated
  7. washwashed with water, brine
  8. dry with materialdried over MgSO4
  9. concentrationconcentrated
  10. distillationChromatography (silica gel, cyclohexane/diethyl ether: 90/10) followed by distillation under reduced pressure

Sources & evidence

ORD record
ord-7f1371f063b945518115580ca4601ce9
Source dataset
uspto-grants-1997_12
Patent number
US05693668

Reaction notes

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