Methanol → 5,8-Dihydro-5,8-epoxynaphtho[2,3-d]-1,3-dioxole

HRID 28788

Reaction equation

HRID 28788 reaction equation
[O:1]1[CH:5]=[CH:4][CH:3]=[CH:2]1.[Li][CH2:7][CH2:8][CH2:9][CH3:10].[CH3:11][OH:12].[OH2:13].[C:14]1([CH3:20])C=CC=CC=1>>[O:1]1[CH:5]2[CH:14]=[CH:20][CH:2]1[C:3]1[C:4]2=[CH:10][C:9]2[O:12][CH2:11][O:13][C:8]=2[CH:7]=1

Participants

6

Reactant 5

HCID 887MethanolHCID 962WaterHCID 1140TolueneHCID 8029FuranHCID 178418339Butyllithium

Product 1

HCID 147704315,8-Dihydro-5,8-epoxynaphtho[2,3-d]-1,3-dioxoleYield 54%

Conditions

Temperature
-78 °C

Procedure

To 3,4-dibromobenzo-1,3-dioxolane (1.54 g, 5.50 mmol) and furan (4 g, 58.8 mmol) in PhMe (55 mL) at −78° C. was added BuLi (2.2 mL, 2.5M in hexanes, 5.5 mmol) dropwise. The reaction was stirred for two hours at −78° C. and the allowed to warm to rt. After 3 hours, MeOH (2 mL) was added and the reaction mixture was poured into water. The organic layer was separated and the aqueous layer was extracted three times with Et2O. The combined organic layers were washed with brine, dried over MgSO4, and concentrated. Recrystallization from hexanes gave 25 (560 mg, 54%) as white crystals). Rf=0.47 on silica gel (30% ethyl acetate:hexanes); mp 111-112° C. (Et2O); IR (KBr, cm−1) 2895, 1455, 1292, 1138, 1038, 1014, 848; 1H NMR (400 MHz, CDCl3) δ 7.02 (2H, dd, J=0.9, 0.9 Hz), 6.82 (2H, s), 5.92 (1H, d, J=1.5 Hz), 5.87 (1H, d, J=1.5 Hz), 5.62 (2H, s); 13C NMR (400 MHz, CDCl3) δ 144.3, 143.3, 103.9, 101.1, 82.4. HRMS calcd for C11H02 (M+): 188.0473. Found: 188.0463.

Workup

  1. temperatureto warm to rt
  2. waitAfter 3 hours
  3. customThe organic layer was separated
  4. extractionthe aqueous layer was extracted three times with Et2O
  5. washThe combined organic layers were washed with brine
  6. dry with materialdried over MgSO4
  7. concentrationconcentrated
  8. customRecrystallization from hexanes

Sources & evidence

ORD record
ord-447854b9ddb2429c8ad5ae9ef463a310
Source dataset
uspto-grants-2008_09
Patent number
US07420003B2

Linked notes

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