Ethyl trifluoroacetate → 5,5-Diethoxy-1,1,1-trifluoro-pent-3-yn-2-one
Reaction equation
[CH2:1]([O:3][CH:4]([O:7][CH2:8][CH3:9])[C:5]#[CH:6])[CH3:2].[Li]CCCC.C([O:17][C:18](=O)[C:19]([F:22])([F:21])[F:20])C>C1COCC1>[CH2:1]([O:3][CH:4]([O:7][CH2:8][CH3:9])[C:5]#[C:6][C:18](=[O:17])[C:19]([F:22])([F:21])[F:20])[CH3:2]Participants
5
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
A mixture of 3,3-Diethoxy-propyne (0.98 g, 7.64 mmol) in THF (20 ml) was cooled to −78 C under Ar. A solution of n-BuLi (2.0M in cyclohexane, 4.2 ml, 8.40 mmol) was added. After 30 min., Trifluoroacetic acid ethyl ester (1.19 g, 8.40 mmol) was added. After 1 h, the reaction was quenched by dilution with 1N HCl, warmed to room temperature and extracted into EtOAc. The organic layer was washed with brine, dried over sodium sulfate, filtered and evaporated. The residue was purified by flash chromatography (0-40% EtOAc in Hexanes) to give product, 0.51 g (30%).