Ethyl Bromide → 2-Acetoxy-2-acetylbutanoic-acid-tert-butylester

HRID 984541Notes

Reaction equation

HRID 984541 reaction equation
[C:1]([O:5][C:6](=[O:15])[CH:7]([O:11][C:12](=[O:14])[CH3:13])[C:8]([CH3:10])=[O:9])([CH3:4])([CH3:3])[CH3:2].[H-].[Na+].[CH2:18](Br)[CH3:19]>CN(C=O)C>[C:1]([O:5][C:6](=[O:15])[C:7]([O:11][C:12](=[O:14])[CH3:13])([C:8](=[O:9])[CH3:10])[CH2:18][CH3:19])([CH3:2])([CH3:3])[CH3:4]

Participants

5

Reactant 3

HCID 6332Ethyl BromideHCID 24758Sodium hydrideHCID 11736056Tert-butyl 2-acetoxyacetoacetate

Product 1

HCID 225593872-Acetoxy-2-acetylbutanoic-acid-tert-butylesterYield 79%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

According to the general alkylation method, tert-butyl-2-acetoxy-aceto-acetate (219a) (1.08 g, 5.00 mmol), NaH (156 mg, 6.5 mmol) and ethylbromide (also propyl and pentyl) (373 μL, 549 mg, 5.00 mmol) were reacted in DMF (10 mL) to give 2-acetoxy-2-acetylbutanoic-acid-tert-butylester (250g) (970 mg, 3.97 mmol, 79%) as a slightly yellow oil. Then, 250 g (1.40 g, 5.73 mmol) and 109 mg (0.57 mmol) p-TsOH.H2O were stirred in 18.0 mL benzene according to decarboxylation method A. Kugelrohr distillation gave 486 mg (3.4 mmol, 59%) of 251 g as a colorless oil.

Sources & evidence

ORD record
ord-83c1c7bf2f3d433082562b4d9aef2c9f
Source dataset
uspto-grants-2005_03
Patent number
US06867333B2

Reaction notes

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