Isobutylene → 1-Ethenyl-4-(2-methoxypropan-2-yl)benzene

HRID 1525349Notes

Reaction equation

HRID 1525349 reaction equation
CC(=C)C.[CH3:5]/[CH:6]=[C:7](/[CH:9]=[CH:10]/[CH:11]=[C:12]([CH3:14])[CH3:13])\[CH3:8].[CH3:15]C(=CC=CC(C)=CC)C.[C:25](=[O:28])(O)[O-].[Na+]>>[CH3:25][O:28][C:12]([C:11]1[CH:5]=[CH:6][C:7]([CH:8]=[CH2:15])=[CH:9][CH:10]=1)([CH3:14])[CH3:13]

Participants

5

Reactant 4

HCID 8255IsobutyleneHCID 126582,6-Dimethyl-2,4,6-octatrieneHCID 516892Sodium BicarbonateHCID 53688212,4,6-Octatriene, 2,6-dimethyl-, (4E,6E)-

Product 1

HCID 184004161-Ethenyl-4-(2-methoxypropan-2-yl)benzene

Procedure

The following examples show that conjugated diene units can also be incorporated in butyl elastomers by carbocationic copolymerization with isobutylene. Technical grade (80%) alloocimene, (2,6-dimethyl-2,4,6-octatriene) of 95.6% actual purity level which was purchased from Aldrich and dried by column chromatography using aluminum oxide (neutral, Brockmann I activity (Aldrich) and degassed by freeze-pump-thaw technique. Isobutylene (IB), 99% purity and methyl chloride (MeCl), 99.5% purity (Matheson TRIGAS) were condensed from gas phase after drying it by passing through a column filled with BaO/CaCl2. Hexane(s) (Mallinckrodt Chemicals with 98.5% minimum purity) was freshly distilled off CaH2 (Aldrich). Di-tert-butylpyridine (DtBP, 97%, TIC), N,N-Dimethyl acetamide (DMA, 99.8%, anhydrous, Aldrich) and titanium tetrachloride (TiCl4, 99.9%, Aldrich) were used as received. p-Vinylcumyl methyl ether (inimer) was synthesized based on the procedure described in (C. Paulo, J. E. Puskas, Macromolecules 2001, 34, 734-739). It was purified by column chromatography using neutral Brockmann activity I alumina (Aldrich) and n-pentane. 2-Chloro-2,4,4-trimethylpentane (TMPCl) was made by hydrochlorination of 2,4,4-trimethylpent-1-ene (TMP-1, Acros). After completion of the reaction, solution was neutralized by the slow addition of sodium bicarbonate, dried over CaH2 and filtered. It was degassed with freeze-pump-thaw cycles.

Workup

  1. customdried by column chromatography
  2. customdegassed by freeze-pump-thaw technique
  3. customcondensed from gas phase
  4. customafter drying it
  5. additionfilled with BaO/CaCl2
  6. distillationHexane(s) (Mallinckrodt Chemicals with 98.5% minimum purity) was freshly distilled off CaH2 (Aldrich)
  7. customIt was purified by column chromatography
  8. customAfter completion of the reaction, solution
  9. customdried over CaH2
  10. filtrationfiltered
  11. customIt was degassed with freeze-pump-thaw cycles

Sources & evidence

ORD record
ord-6f5bbe10b727477082db838128b23ec9
Source dataset
uspto-grants-2015_07
Patent number
US09079980B2

Reaction notes

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