Isobutyraldehyde → 1-(3,3-Dimethyl-2,3-dihydrobenzofuran-5-yl)-2-methyl-propan-1-ol

HRID 1790210Notes

Reaction equation

HRID 1790210 reaction equation
Br[C:2]1[CH:3]=[CH:4][C:5]2[O:9][CH2:8][C:7]([CH3:11])([CH3:10])[C:6]=2[CH:12]=1.[Li]CCCC.[CH:18](=[O:22])[CH:19]([CH3:21])[CH3:20].[Cl-].[NH4+]>C1COCC1>[CH3:10][C:7]1([CH3:11])[C:6]2[CH:12]=[C:2]([CH:18]([OH:22])[CH:19]([CH3:21])[CH3:20])[CH:3]=[CH:4][C:5]=2[O:9][CH2:8]1

Participants

6

Reactant 4

HCID 6561IsobutyraldehydeHCID 25517Ammonium ChlorideHCID 53235955-Bromo-3,3-dimethyl-2,3-dihydro-1-benzofuranHCID 178418339Butyllithium

Product 1

HCID 220414081-(3,3-Dimethyl-2,3-dihydrobenzofuran-5-yl)-2-methyl-propan-1-olYield 106.7%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a solution of 5-bromo-3,3-dimethyl-2,3-dihydro-benzofuran (2.03 g, 8.93 mmol) in dry THF (10 mL) at −78° C., under argon, was added dropwise n-BuLi (1.6 M in hexane, 13.4 mmol, 8.38 mL). The mixture was stirred for 5 minutes then isobutyraldehyde (1.22 mL, 8.38 mmol) was added and the mixture was slowly warmed up to room temperature and stirred overnight at room temperature. Aqueous ammonium chloride was added and the solution extracted with ethylacetate and the organic extract was dried (Mg2SO4), filtered and evaporated. The residue was purified on silica gel (0% to 20% ethyl acetate in hexane) to give 1.97 g of 1-(3,3-dimethyl-2,3-dihydro-benzofuran-5-yl)-2-methyl-propan-1-ol (100%). 1H NMR (300 MHz; CDCl3): δ 0.77 (d, J=6.6 Hz, 3 H), 0.90 (d, J=6.6 Hz, 3 H), 1.33 (s, 6 H), 1.95 (m, 1 H), 4.23 (s, 2 H), 4.28 (d, J=7.2 Hz, 2 H), 6.72 (d, J=8.4 Hz, 1 H), 7.03 (dd, J=8.1 Hz and 1.8 Hz, 1 H), 7.06 (d, J=1.5 Hz, 1 H).

Workup

  1. stirringstirred overnight at room temperature
  2. extractionthe solution extracted with ethylacetate
  3. extractionthe organic extract
  4. dry with materialwas dried (Mg2SO4)
  5. filtrationfiltered
  6. customevaporated
  7. customThe residue was purified on silica gel (0% to 20% ethyl acetate in hexane)

Sources & evidence

ORD record
ord-8ced0d5f185d429ab03b60c0c8ee990d
Source dataset
uspto-grants-2006_07
Patent number
US07071218B2

Reaction notes

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