Methyl acetoacetate → 4-Hydroxy-6-(4-methoxyphenyl)-5,6-dihydro-2H-pyran-2-one

HRID 357803Notes

Reaction equation

HRID 357803 reaction equation
[C:1]([O:7][CH3:8])(=[O:6])[CH2:2][C:3]([CH3:5])=[O:4].[H-].[Na+].C([Li])CCC.[CH3:16][O:17][C:18]1[CH:25]=[CH:24][C:21](C=O)=[CH:20][CH:19]=1>CCCCCC.O1CCCC1>[OH:4][C:3]1[CH2:5][CH:8]([C:21]2[CH:24]=[CH:25][C:18]([O:17][CH3:16])=[CH:19][CH:20]=2)[O:7][C:1](=[O:6])[CH:2]=1

Participants

7

Reactant 4

HCID 7757Methyl acetoacetateHCID 24758Sodium hydrideHCID 312444-MethoxybenzaldehydeHCID 178418339Butyllithium

Product 1

HCID 546878394-Hydroxy-6-(4-methoxyphenyl)-5,6-dihydro-2H-pyran-2-one

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolventHCID 8058HexaneSolvent

Conditions

Temperature
0 °C

Procedure

The title compound was prepared as described in General Method 1 using 5 mL of methyl acetoacetate, 2.0 g of NaH 60% dispersion in oil, 25 mL of 2.0M n-butyl lithium in hexane, 7.0 mL of 4-methoxybenzaldehyde and 150 mL of tetrahydrofuran. After addition of the aldehyde, the reaction was stirred for 15 minutes at 0° C. then allowed to warm to room temperature overnight. The crude product was triturated from diethyl ether to afford a solid (m.p.159°-162° C. (dec.)). 1H NMR (CDCl3) δ 2.91 (dd, 2 H), 3.57 (dd, 2 H), 3.83 (s, 3 H), 5.66 (dd, 1 H), 6.93-6.97 (m, 2 H), 7.30-7.34 (m, 2 H).

Workup

  1. temperatureto warm to room temperature overnight
  2. customThe crude product was triturated from diethyl ether

Sources & evidence

ORD record
ord-953ff631718b4dab95270581e2d3591b
Source dataset
uspto-grants-1998_11
Patent number
US05840751

Reaction notes

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