Methanol → Acetic acid, 2-(1,4-dioxaspiro(4.5)dec-8-ylidene)-, ethyl ester

HRID 1292957

Reaction equation

HRID 1292957 reaction equation
[CH2:1]1[CH2:5][O:4][CH2:3][CH2:2]1.[H-].[Li+].[CH2:8]1[O:18][C:11]2([CH2:16][CH2:15][C:14](=O)[CH2:13][CH2:12]2)[O:10][CH2:9]1.C[OH:20]>O>[O:10]1[C:11]2([CH2:16][CH2:15][C:14](=[CH:2][C:3]([O:4][CH2:5][CH3:1])=[O:20])[CH2:13][CH2:12]2)[O:18][CH2:8][CH2:9]1

Participants

6

Reactant 4

HCID 887MethanolHCID 8028TetrahydrofuranHCID 62714Lithium hydrideHCID 5674151,4-Dioxaspiro[4.5]decan-8-one

Product 1

HCID 373318Acetic acid, 2-(1,4-dioxaspiro(4.5)dec-8-ylidene)-, ethyl esterYield 93%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

To a solution of THF (18 mL) under argon was added 0.38 g (47.8 mmol, 5 equiv) of LiH, followed by slow addition of 8.78 g (47.8 mmol, 5 equiv) of triethyl phosphonoacetate. The solution was stirred at rt for 1 h and 1.49 g (9.6 mmol, 1 equiv) of 1,4-cyclohexanedione mono-ethylene ketal was added and the solution was heated at 65° C. for 16 h. Upon cooling the solution was treated with MeOH (10 mL) and water (5 mL) and concentrated in vacuo. The resulting yellow oil was purified by silica gel chromatography eluting with 4:1 Hex/EtOAc to yield 1.89 g (93%) of a clear oil. 1H-NMR (CDCl3-d) δ 5.67 (s, 1H), 4.16 (t, 2H), 3.99 (m, 4H), 3.02 (m, 2H), 2.39 (m, 2H), 1.78 (m, 4H), 1.29 (t, 3H); LCMS RT=2.56 min; [M+H]+=226.9.

Workup

  1. temperaturethe solution was heated at 65° C. for 16 h
  2. temperatureUpon cooling the solution
  3. concentrationconcentrated in vacuo
  4. customThe resulting yellow oil was purified by silica gel chromatography
  5. washeluting with 4:1 Hex/EtOAc

Sources & evidence

ORD record
ord-ddeb1a6f4b9744bf933637a33a3216f9
Source dataset
uspto-grants-2007_07
Patent number
US07238701B2

Linked notes

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