Diisopropylamine → Methyl 4-(2-t-butoxycarbonyl-vinyl)-benzoate

HRID 1180799Notes

Reaction equation

HRID 1180799 reaction equation
N(C(C)C)C(C)C.[Li]CCCC.[Li+].CC([N-]C(C)C)C.[C:21]([O:24][C:25]([CH3:28])([CH3:27])[CH3:26])(=[O:23])[CH3:22].[CH:29]([C:31]1[CH:40]=[CH:39][C:34]([C:35]([O:37][CH3:38])=[O:36])=[CH:33][CH:32]=1)=O.ClC1N=C(OC)N=C(OC)N=1.[NH4+].[Cl-]>C1COCC1.CCOC(C)=O>[C:25]([O:24][C:21]([CH:22]=[CH:29][C:31]1[CH:40]=[CH:39][C:34]([C:35]([O:37][CH3:38])=[O:36])=[CH:33][CH:32]=1)=[O:23])([CH3:28])([CH3:27])[CH3:26]

Participants

10

Reactant 7

HCID 7912DiisopropylamineHCID 10908tert-Butyl acetateHCID 15294Methyl 4-FormylbenzoateHCID 184502-Chloro-4,6-dimethoxy-1,3,5-triazineHCID 25517Ammonium ChlorideHCID 2724682Lithium diisopropylamideHCID 178418339Butyllithium

Product 1

HCID 53900295Methyl 4-(2-t-butoxycarbonyl-vinyl)-benzoateYield 49.3%

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolvent3×HCID 8857Ethyl AcetateSolvent

Procedure

To a solution of anhydrous i-Pr2NH (1.76 ml, 12.49 mmol) in anhydrous THF (30 ml) stirred at 0° C. under nitrogen, was slowly added a solution of n-BuLi (5.36 ml, 13.40 mmol, 2.5 M in hexane). After 30 min, LDA was cooled to −78° C. and t-butyl acetate (1.64 ml, 12.18 mmol) was added dropewise. After 30 min, a solution of methyl 4-formylbenzoate (1.00 g, 6.09 mmol) in anhydrous THF (10 ml) was slowly added. After 2 h, a solution of 2-chloro-4,6-dimethoxy-1,3,5-triazine (1.604 g, 9.14 mmol) in anhydrous THF (10 ml) was added. Then, the temperature was allowed to warm up to room temperature overnight. A suspension appeared. The reaction mixture was poured into a saturated aqueous solution of NH4Cl, and diluted with AcOEt. After separation, the organic layer was successively washed with H2O and brine, dried over MgSO4, filtered and concentrated. The crude product was purified by flash chromatography on silica gel (AcOEt/hexane:10/90→15/85) to give the title product VI (785 mg, 3.00 mmol, 49% yield) as a white solid. 1H NMR (300 MHz, CDCl3) δ(ppm): AB system (δA=8.04, δB=7.57, J=8.4 Hz, 4H), 7.60 (d, J=15.4 Hz, 1H), 6.46 (d, J=15.8 Hz, 1H), 3.93 (s, 3H), 1.54 (s, 9H). 13C NMR (75 MHz, CDCl3) δ(ppm): 166.72, 166.01, 142.31, 139.18, 131.33, 130.26, 127.99, 122.87, 81.11, 52.46, 28.40.

Workup

  1. waitAfter 30 min
  2. waitAfter 2 h
  3. customAfter separation
  4. washthe organic layer was successively washed with H2O and brine
  5. dry with materialdried over MgSO4
  6. filtrationfiltered
  7. concentrationconcentrated
  8. customThe crude product was purified by flash chromatography on silica gel (AcOEt/hexane:10/90→15/85)

Sources & evidence

ORD record
ord-7a26a8a3bd504d7e9ccf4afbc8b58522
Source dataset
uspto-grants-2007_10
Patent number
US07282608B2

Reaction notes

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