Triethylamine → 2,6,6-Trimethyl-5,5-bis(trimethylsilyl)-5,6-disilahept-2-yl Bicyclo[2.2.1]hept-5-ene-2-carboxylate

HRID 277656Notes

Reaction equation

HRID 277656 reaction equation
[CH:1]12[CH2:7][CH:4]([CH:5]=[CH:6]1)[CH2:3][CH:2]2[C:8]([OH:10])=[O:9].S(Cl)(Cl)=O.[CH3:15][C:16](O)([CH2:18][CH2:19][Si:20]([Si:29]([CH3:32])([CH3:31])[CH3:30])([Si:25]([CH3:28])([CH3:27])[CH3:26])[Si:21]([CH3:24])([CH3:23])[CH3:22])[CH3:17].C(N(CC)CC)C>O.O1CCCC1>[CH:1]12[CH2:7][CH:4]([CH:5]=[CH:6]1)[CH2:3][CH:2]2[C:8]([O:10][C:16]([CH3:17])([CH2:18][CH2:19][Si:20]([Si:29]([CH3:32])([CH3:31])[CH3:30])([Si:21]([CH3:24])([CH3:23])[CH3:22])[Si:25]([CH3:28])([CH3:27])[CH3:26])[CH3:15])=[O:9]

Participants

7

Reactant 4

HCID 8471TriethylamineHCID 24386Thionyl ChlorideHCID 789495-Norbornene-2-carboxylic acidHCID 226255582,6,6-Trimethyl-5,5-bis(trimethylsilyl)-5,6-disilaheptan-2-ol

Product 1

HCID 226255602,6,6-Trimethyl-5,5-bis(trimethylsilyl)-5,6-disilahept-2-yl Bicyclo[2.2.1]hept-5-ene-2-carboxylateYield 72%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent

Conditions

Temperature
50 °C

Procedure

An oven-dried reaction flask equipped for magnetic stirring and fitted with a reflux condenser was flushed with nitrogen and charged with of bicyclo[2.2.1]hept-5-ene-2-carboxylic acid (55.3 g, 0.4 mol) and thionyl chloride (190.0 g, 1.6 mol). The mixture was heated at 50° C. for 2 hours. Excess thionyl chloride was evaporated under reduced pressure, of tetrahydrofuran (20 mL) was added to the concentrate, and volatiles were again separated under reduced pressure. To the amber concentrate, of tetrahydrofuran (200 mL), 2,6,6-Trimethyl-5,5-bis(trimethylsilyl)-5,6-disilaheptan-2-ol (33.5 g, 0.1 mol), and triethylamine (41.0 g, 0.4 mol) were added, and the reaction mixture was heated at 50° C. for 24 hours. The reaction mixture was poured into water (200 mL), the organic phase was separated, and the aqueous phase was extracted three 50 mL portions of diethyl ether. The combined organic phases were washed with one 50 mL portion of saturated aqueous sodium chloride and dried over magnesium sulfate. The mixture was filtered, and the filtrate was concentrated under reduced pressure. The crude product was purified by column chromatography (90:10 hexanes:diethyl ether, Rf=0.47 and 0.58), affording the title compound (32.6 g, 72%) as a clear, colorless oil. The 1H, 13C, and 29Si NMR spectra of the product were consistent with the structure of the title compound as an approximately 55:45 mixture of the endo and exo isomers.

Workup

  1. customAn oven-dried reaction flask
  2. customequipped
  3. customfitted with a reflux condenser
  4. customwas flushed with nitrogen
  5. customExcess thionyl chloride was evaporated under reduced pressure, of tetrahydrofuran (20 mL)
  6. additionwas added to the concentrate, and volatiles
  7. customwere again separated under reduced pressure
  8. additionwere added
  9. temperaturethe reaction mixture was heated at 50° C. for 24 hours
  10. customthe organic phase was separated
  11. extractionthe aqueous phase was extracted three 50 mL portions of diethyl ether
  12. washThe combined organic phases were washed with one 50 mL portion of saturated aqueous sodium chloride
  13. dry with materialdried over magnesium sulfate
  14. filtrationThe mixture was filtered
  15. concentrationthe filtrate was concentrated under reduced pressure
  16. customThe crude product was purified by column chromatography (90:10 hexanes:diethyl ether, Rf=0.47 and 0.58)

Sources & evidence

ORD record
ord-9003b14a482a4ea6b2005d28bbcdc567
Source dataset
uspto-grants-2002_03
Patent number
US06358675B1

Reaction notes

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