1,2-Dibromoethane → 4,4,5,5-Tetramethyl-2-(2-methylnaphthalen-1-yl)-1,3,2-dioxaborolane

HRID 513907

Reaction equation

HRID 513907 reaction equation
BrCCBr.[Mg].Br[C:7]1[C:16]2[C:11](=[CH:12][CH:13]=[CH:14][CH:15]=2)[CH:10]=[CH:9][C:8]=1[CH3:17].C(O[B:22]1[O:26][C:25]([CH3:28])([CH3:27])[C:24]([CH3:30])([CH3:29])[O:23]1)(C)C>C1COCC1.O>[CH3:29][C:24]1([CH3:30])[C:25]([CH3:28])([CH3:27])[O:26][B:22]([C:7]2[C:16]3[C:11](=[CH:12][CH:13]=[CH:14][CH:15]=3)[CH:10]=[CH:9][C:8]=2[CH3:17])[O:23]1

Participants

7

Reactant 4

HCID 78391,2-DibromoethaneHCID 757541-Bromo-2-methylnaphthaleneHCID 50177412-Isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolaneHCID 5462224Magnesium

Product 1

HCID 222401864,4,5,5-Tetramethyl-2-(2-methylnaphthalen-1-yl)-1,3,2-dioxaborolane

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent

Procedure

1,2-Dibromoethane (˜0.3 ml) was added to 6.10 g (250 mmol) magnesium turnings in 1000 cm3 of THF. This mixture was stirred for 10 min, and then 55.3 g (250 mmol) of 1-bromo-2-methylnaphthalene was added for 1 h by vigorous stirring at room temperature for 3.5 h. Thereafter, 46.5 g (250 mmol) of 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane was added in one portion. The resulting mixture was stirred for 15 minutes and then was poured into 1000 cm3 of cold water. The product was extracted with 3×300 ml of ethyl acetate. The organic layer was separated, washed by water, brine, then dried over MgSO4, and, finally, evaporated to dryness. The resulting white solid was washed by 2×75 ml of pentane and dried in vacuum. Yield 47.3 g (70%). Anal. calc. for C17H21BO2: C, 76.14; H, 7.89. Found: C, 76.31; H, 8.02. 1H NMR (CDCl3): 8.12 (m, 1H, 8-H), 7.77 (m, 1H, 5-H), 7.75 (d, J=8.4 Hz, 1H, 4-H), 7.44 (m, 1H, 7-H), 7.38 (m, 1H, 6-H), 7.28 (d, J=8.4 Hz, 1H, 3-H), 2.63 (s, 3H, 2-Me), 1.48 (s, 12H, CMe2CMe2).

Workup

  1. stirringby vigorous stirring at room temperature for 3.5 h
  2. stirringThe resulting mixture was stirred for 15 minutes
  3. extractionThe product was extracted with 3×300 ml of ethyl acetate
  4. customThe organic layer was separated
  5. washwashed by water, brine
  6. dry with materialdried over MgSO4
  7. customfinally, evaporated to dryness
  8. washThe resulting white solid was washed by 2×75 ml of pentane
  9. customdried in vacuum

Sources & evidence

ORD record
ord-d2c1c28525a64022a58b06ba8a6e709b
Source dataset
uspto-grants-2015_08
Patent number
US09102773B2

Linked notes

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