Sodium Carbonate → 4-(7-Bromo-1,3-benzodioxol-4-yl)-4-methyl-2-oxo-valeric acid-ethyl ester

HRID 2215480Notes

Reaction equation

[Br:1][C:2]1[C:7]2[O:8][CH2:9][O:10][C:6]=2[C:5]([C:11](O)([CH3:13])[CH3:12])=[CH:4][CH:3]=1.[CH2:15]([O:17][C:18](=[O:26])[C:19]([O:21][Si](C)(C)C)=[CH2:20])[CH3:16].[Sn+6].[Cl-].C(=O)([O-])[O-].[Na+].[Na+]>ClCCl>[CH2:15]([O:17][C:18](=[O:26])[C:19](=[O:20])[CH2:21][C:11]([C:5]1[C:6]2[O:10][CH2:9][O:8][C:7]=2[C:2]([Br:1])=[CH:3][CH:4]=1)([CH3:13])[CH3:12])[CH3:16]

Participants

Conditions

Temperature: -70 °C

Procedure

1.77 g of 2-(7-bromobenzo[1,3]dioxol-4-yl)-propan-2-ol and 2.82 g of 2-trimethylsilyloxy-acrylic acid-ethyl ester (WO 00/32584) in 36 ml of dichloromethane are mixed at −70° C. with 1.10 ml of tin(VI)chloride. It is stirred for 20 minutes at −70° C. and then added to saturated sodium carbonate solution. It is extracted with dichloromethane, washed with water, dried and concentrated by evaporation in a vacuum. 3.15 g of 4-(7-bromo-1,3-benzodioxol-4-yl)-4-methyl-2-oxo-valeric acid-ethyl ester is obtained as a crude product. The latter is reacted for 4 hours at room temperature in 57 ml of a mixture that consists of 1N sodium hydroxide solution in ethanol/water. The batch is added to water, extracted with ether and then the aqueous phase is acidified with hydrochloric acid. It is extracted with ethyl acetate, washed with water, dried with sodium sulfate and concentrated by evaporation in a vacuum. 2.1 g of 4-(7-bromo-1,3-benzodioxol-4-yl)-4-methyl-2-oxo-valeric acid is obtained as a yellow oil.

Workup

extractionIt is extracted with dichloromethane
washwashed with water
customdried
concentrationconcentrated by evaporation in a vacuum

Sources & evidence

ORD record: ord-f6201d9cc17049aaa18250a07f0cedd9
Source dataset: uspto-grants-2006_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07109212B2

Reaction notes

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