Ethyl Acetate → Ethyl 2-hydroxy-4-methyl-2-(trifluoromethyl)pent-4-enoate

HRID 430460

Reaction equation

[CH2:1](Br)[C:2](=[CH2:4])[CH3:3].[CH2:6]([O:8][C:9](=[O:16])[C:10]([C:12]([F:15])([F:14])[F:13])=[O:11])[CH3:7].[Cl-].[NH4+].C(OCC)(=O)C>O1CCCC1.[Cl-].[Zn+2].[Cl-].[Mn]>[CH2:6]([O:8][C:9](=[O:16])[C:10]([OH:11])([C:12]([F:13])([F:15])[F:14])[CH2:3][C:2](=[CH2:1])[CH3:4])[CH3:7]

Participants

Conditions

Temperature: 0 °C

Procedure

1.3 g of anhydrous zinc chloride and 13.2 g of granular manganese are heated to boiling in 100 ml of tetrahydrofuran and boiled with 0.2 ml of methallyl bromide for 30 minutes. Then, the solution of 25 g of methallylbromide and 17 g of trifluoropyruvic acid ethyl ester in 80 ml of tetrahydrofuran is added in drops at boiling heat over two hours and boiled for another hour. Then, it is added to saturated ammonium chloride solution and 300 ml of ethyl acetate while being cooled with ice, stirred for 30 minutes at 0° C., and the separated ethyl acetate phase is washed with saturated ammonium chloride solution and three times with water. The solvent is dried (Na2SO4) and concentrated by evaporation, and the residue is distilled in a vacuum. 17.6 g of 2-hydroxy-4-methylene-2-trifluoromethyl-valeric acid ethyl ester, boiling point 48° C., 1 hPa, is obtained.

Workup

temperatureat boiling heat over two hours
waitboiled for another hour
temperaturewhile being cooled with ice
washthe separated ethyl acetate phase is washed with saturated ammonium chloride solution and three times with water
dry with materialThe solvent is dried (Na2SO4)
concentrationconcentrated by evaporation
distillationthe residue is distilled in a vacuum

Sources & evidence

ORD record: ord-605ea9751b734934af7fb3bb1d09a996
Source dataset: uspto-grants-2001_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06323199B1

Linked notes

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