Diethyl Malonate → Acetic Anhydride

HRID 1358243Notes

Reaction equation

HRID 1358243 reaction equation
[CH2:1]([O:3][C:4](=[O:11])[CH2:5][C:6]([O:8][CH2:9][CH3:10])=[O:7])[CH3:2].CC(C)([O-:15])C.[K+].ClC[C:20]1[C:24]2[C:25]([CH3:30])=[CH:26][CH:27]=[C:28]([Cl:29])[C:23]=2[O:22][CH:21]=1>CN(C)C=O>[C:9]([O:8][C:6](=[O:7])[CH3:5])(=[O:15])[CH3:10].[Cl:29][C:28]1[C:23]2[O:22][CH:21]=[C:20]([CH:5]([C:6]([O:8][CH2:9][CH3:10])=[O:7])[C:4]([O:3][CH2:1][CH3:2])=[O:11])[C:24]=2[C:25]([CH3:30])=[CH:26][CH:27]=1

Participants

6

Reactant 3

HCID 7761Diethyl MalonateHCID 18184290HCID 18184290, compoundHCID 23665647Potassium tert-butoxide

Product 2

HCID 7918Acetic AnhydrideHCID 18184320HCID 18184320, compound

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent2×

Procedure

Malonic acid diethyl ester (8.5 g) was dissolved in dimethylformamide (75 mL) followed by addition of potassium tert-butoxide (5.9 g). After stirring for 15 min at room temperature, a solution of 3-chloromethyl-7-chloro-4-methylbenzofuran (3.8 g, prepared analogously to the 5-fluoro analogue as described in Example, 2) in dimethylformamide (25 mL) was added dropwise. After stirring for 2 hours the reaction mixture was poured onto ice-water. Standard work-up with acetyl acetate gave a yellow oil (10 g) of diethyl 2-(7-chloro-4-methylbenzofuran-3-yl)malonate, sufficiently pure for further synthesis.

Workup

  1. additionwas added dropwise
  2. stirringAfter stirring for 2 hours the reaction mixture
  3. additionwas poured onto ice-water

Sources & evidence

ORD record
ord-49399576c1e94afbb99904f1588247f7
Source dataset
uspto-grants-2003_07
Patent number
US06596722B2

Reaction notes

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