Phthalimide → tert-butyl 4-[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)acetyl]piperazine-1-carboxylate
Reaction equation
[C:1]1(=[O:11])[NH:5][C:4](=[O:6])[C:3]2=[CH:7][CH:8]=[CH:9][CH:10]=[C:2]12.Cl[CH2:13][C:14]([N:16]1[CH2:21][CH2:20][N:19]([C:22]([O:24][C:25]([CH3:28])([CH3:27])[CH3:26])=[O:23])[CH2:18][CH2:17]1)=[O:15].C(N(C(C)C)CC)(C)C>[I-].C([N+](CCCC)(CCCC)CCCC)CCC.C(Cl)Cl>[O:6]=[C:4]1[C:3]2[C:2](=[CH:10][CH:9]=[CH:8][CH:7]=2)[C:1](=[O:11])[N:5]1[CH2:13][C:14]([N:16]1[CH2:21][CH2:20][N:19]([C:22]([O:24][C:25]([CH3:28])([CH3:27])[CH3:26])=[O:23])[CH2:18][CH2:17]1)=[O:15]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 2
Procedure
Phthalimide (33 mg, 0.23 mmol) was treated with tert-butyl 4-(2-chloroacetyl)piperazine-1-carboxylate (80.5 mg, 0.32 mmol), tetrabutylammonium iodide (TBAI, 84 mg, 2.3 mmol), diisopropylethylamine (DIEA, 0.20 mg, 1.14 mmol) in anhydrous CH2Cl2 (10 mL) for 24 h at 40° C. The mixture was partitioned between CH2Cl2 and water. The organic phase was separated, dried over MgSO4, filtered, concentrated, and purified by flash chromatography on a silica gel column with elution of EtOAc/hexane (1:1) to give the title compound (57.1 mg, 67% yield). C19H23N3O5; white solid; TLC (EtOAc/hexane=1:1) Rf=0.2; 1H NMR (400 MHz, CDCl3) δ 7.85-7.87 (2H, m), 7.70-7.72 (2H, m), 4.49 (2H, s), 3.51-3.57 (6H, m), 3.44 (2H, d, J=5.2 Hz), 1.46 (9H, d, J=4.8 Hz).
Workup
- customThe mixture was partitioned between CH2Cl2 and water
- customThe organic phase was separated
- dry with materialdried over MgSO4
- filtrationfiltered
- concentrationconcentrated
- custompurified by flash chromatography on a silica gel column with elution of EtOAc/hexane (1:1)
Sources & evidence
- ORD record
- ord-4ef059a068b84f648e308c16e253ed43
- Source dataset
- uspto-grants-2016_03
- Patent number
- US09278982B2
Reaction notes
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