1-Bromopropane → 2-Acetoxy-2-acetyl-pentanoic-acid-tert-butylester

HRID 984543Notes

Reaction equation

HRID 984543 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)[CH2:19][CH3:20]>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][CH2:19][CH3:20])([CH3:2])([CH3:3])[CH3:4]

Participants

5

Reactant 3

HCID 78401-BromopropaneHCID 24758Sodium hydrideHCID 11736056Tert-butyl 2-acetoxyacetoacetate

Product 1

HCID 225594052-Acetoxy-2-acetyl-pentanoic-acid-tert-butylesterYield 71%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

According to the general alkylation method, tert-butyl-2-acetoxy-aceto-acetate (219a) (7.12 g, 32.9 mmol), NaH (900 mg, 37.5 mmol) and propylbromide (4.05 g, 32.9 mmol) were reacted in DMF (64 mL) to give 2-acetoxy-2-acetyl-pentanoic-acid-tert-butylester (250h) (6.00 g, 23.2 mmol, 71%) as a slightly yellow oil after Kugelrohr distillation at 160° C. and 1.0 mbar. Then, 250h (6.00 g, 23.2 mmol) and 393 mg (2.07 mmol) p-TsOH.H2O were stirred in 60 mL benzene according to decarboxylation method A. Kugelrohr distillation at 1.0 mbar and 150° C., followed by column chromatography (diethylether:petroleum ether=1:8) gave 251h (2.00 g, 12.6 mmol, 54%) as a colorless oil.

Sources & evidence

ORD record
ord-8d56ad4654124fadb8b144811c601981
Source dataset
uspto-grants-2005_03
Patent number
US06867333B2

Reaction notes

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