Ethyl trifluoroacetate → Tert-butyl 4-(2,2,2-trifluoroacetyl)piperazine-1-carboxylate
Reaction equation
[F:1][C:2]([F:9])([F:8])[C:3]([O:5]CC)=O.[CH3:10][C:11]([CH3:22])([O:13][C:14]([N:16]1[CH2:21][CH2:20][NH:19][CH2:18][CH2:17]1)=[O:15])[CH3:12]>>[F:9][C:2]([F:1])([F:8])[C:3]([N:19]1[CH2:18][CH2:17][N:16]([C:14]([O:13][C:11]([CH3:22])([CH3:12])[CH3:10])=[O:15])[CH2:21][CH2:20]1)=[O:5]Participants
Conditions
- Temperature
- 40 °C
Procedure
Ethyl trifluoroacetate (3.9 g, 0.027 mole) was added over 10 minutes to a warm (40° C.) stirred melt of 5.2 g (0.028 mole) 1-[1,1-dimethylethoxycarbonyl]piperazine. The mixture was heated at 120° C. for 2 hours, cooled to room temperature, treated with 1.0 g (0.007 mole) ethyl trifluoroacetate, and reheated for an additional 2 hours. The mixture was allowed to stand 18 hours at room temperature and then was evaporated in vacuo. The residue was dissolved in ether, passed through an alumina-packed column (2.2×16 cm), the eluent collected, washed with dilute aqueous HCl, dried (MgSO4), filtered, and evaporated in vacuo to yield 6.6 g yellow oil which solidified on standin g Recrystallization from hexane gave 6.0 g of white, crystalline solid, m.p. 66°-68° C. Calc. for C11H17F3N2O3 (282.26): C, 46.81; H, 6.07; N, 9.92. Found: C, 46.76; H, 6.40; N, 10.12.
Workup
- temperatureThe mixture was heated at 120° C. for 2 hours
- temperaturecooled to room temperature
- waitto stand 18 hours at room temperature
- customwas evaporated in vacuo
- dissolutionThe residue was dissolved in ether
- customthe eluent collected
- washwashed with dilute aqueous HCl
- dry with materialdried (MgSO4)
- filtrationfiltered
- customevaporated in vacuo
Sources & evidence
- ORD record
- ord-fd649745ba654d83a09ee27cc1f1a1c5
- Source dataset
- uspto-grants-1981_01
- Patent number
- US04247549
Reaction notes
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