Tetramethoxysilane → HCID 12135717, compound

HRID 2086386Notes

Reaction equation

HRID 2086386 reaction equation
[Mg].Br[C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][C:4]=1[CH2:9][CH3:10].[CH2:11]([Si:16](OC)([O:19][CH3:20])[O:17][CH3:18])[CH2:12][CH:13]([CH3:15])[CH3:14].C([Mg]Br)CC(C)C.CO[Si](OC)(OC)OC>O.CCOCC>[CH2:9]([C:4]1[CH:5]=[CH:6][CH:7]=[CH:8][C:3]=1[Si:16]([CH2:11][CH2:12][CH:13]([CH3:15])[CH3:14])([O:19][CH3:20])[O:17][CH3:18])[CH3:10]

Participants

8

Reactant 5

HCID 12682TetramethoxysilaneHCID 160891-Bromo-2-ethylbenzeneHCID 5462224MagnesiumHCID 21924134HCID 21924134, compoundHCID 178418529HCID 178418529, compound

Product 1

HCID 12135717HCID 12135717, compoundYield 35.6%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 3283Diethyl EtherSolvent

Procedure

A 1000 mL round bottomed flask was charged with magnesium turnings (1.97 g, 81.0 mmol, Aldrich) and ether (500 mL, Aldrich). Bromo-2-ethylbenzene (14.0 mL, 101 mmol, Aldrich) was added over 30 minutes. The reaction stirred for three hours at room temperature and became dark brown in color. The contents were refluxed for one hour. The contents were cooled to 0° C. and isoamyl-trimethoxysilane (15.9 g, 82.8 mmol, previously prepared by reaction between isoamyl magnesiumbromide and tetramethylortho-silicate) was added over 25 minutes. The reaction was stirred at room temperature overnight (18 hours) during which time a white precipitate formed. The contents were poured into water (500 mnL), the layers separated and the product extracted into ether (3×150 mL). The combined organic portions were dried (MgSO4), filtered and the solvent removed via rotary evaporation providing 29.6 g crude material. Distillation under reduced pressure (b.p. 109° C., 1.1 mm Hg) produced (2-ethylphenyl)-3-methylbutyl-dimethoxysilane (7.68 g, 28.8 mmol, 35.6% yield); C15H26SiO2 (Mw=266.45); 1H NMR (CDCl3) δ7.7 (m, 1H), 7.3 (m, 1H), 7.2 (m, 2H), 3.5 (s, 6H), 2.8 (q, 2H), 1.4 (m, 1H), 1.2(m, 5H), 0.8(m, 8H); 13C NMR (CDCl3) δ150.5, 135.9, 131.2, 130.3, 128.0, 124.9, 50.3, 31.5, 30.7, 28.6, 21.9, 16.1, 10.9; IR (capillary film) ν3054, 2974, 1590, 1467, 1370, 1200, 1118, 1023, 936, 874 803, MS m/z (relative abundance) 266 (0.02), 195 (100), 163 (59.1), 160 (28.8), 133 (25.5), 105 (11.2), 91 (12.3), 59 (18.4).

Workup

  1. temperatureThe contents were refluxed for one hour
  2. temperatureThe contents were cooled to 0° C.
  3. additionwas added over 25 minutes
  4. stirringThe reaction was stirred at room temperature overnight (18 hours) during which time a white precipitate
  5. customformed
  6. customthe layers separated
  7. extractionthe product extracted into ether (3×150 mL)
  8. dry with materialThe combined organic portions were dried (MgSO4)
  9. filtrationfiltered
  10. customthe solvent removed via rotary evaporation
  11. customproviding 29.6 g crude material
  12. distillationDistillation under reduced pressure (b.p. 109° C., 1.1 mm Hg)

Sources & evidence

ORD record
ord-d541de7efb3145cc83a4c82145988bb8
Source dataset
uspto-grants-2004_04
Patent number
US06723865B2

Reaction notes

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