1-Ethyl-3-(3'-dimethylaminopropyl)carbodiimide → t-Butyl 4-(2,4-difluorobenzoyl)piperazine-1-carboxylate

HRID 2239791

Reaction equation

HRID 2239791 reaction equation
[F:1][C:2]1[CH:10]=[C:9]([F:11])[CH:8]=[CH:7][C:3]=1[C:4]([OH:6])=O.CCN(C(C)C)C(C)C.C1C=CC2N(O)N=NC=2C=1.[N:31]1([C:37]([O:39][C:40]([CH3:43])([CH3:42])[CH3:41])=[O:38])[CH2:36][CH2:35][NH:34][CH2:33][CH2:32]1.CCN=C=NCCCN(C)C>C(Cl)Cl.O>[F:1][C:2]1[CH:10]=[C:9]([F:11])[CH:8]=[CH:7][C:3]=1[C:4]([N:34]1[CH2:33][CH2:32][N:31]([C:37]([O:39][C:40]([CH3:43])([CH3:42])[CH3:41])=[O:38])[CH2:36][CH2:35]1)=[O:6]

Participants

8

Reactant 5

HCID 159081-Ethyl-3-(3'-dimethylaminopropyl)carbodiimideHCID 741022,4-Difluorobenzoic acidHCID 757711-HydroxybenzotriazoleHCID 81531DiisopropylethylamineHCID 143452tert-Butyl piperazine-1-carboxylate

Product 1

HCID 68414338t-Butyl 4-(2,4-difluorobenzoyl)piperazine-1-carboxylate

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6344DichloromethaneSolvent

Procedure

To a solution of 3.0 g (19 mmol) of 2,4-difluorobenzoic acid and 4 mL of DIEA (1.2 equiv.) in 40 mL of dry DCM is added 3.08 g (1.2 equiv) of HOBt and 4.2 g (22.55 mmol) of t-butyl piperazine-1-carboxylate, and the mixture was stirred at RT for 30 min. 4.4 g (11 equiv.) of EDCI are added and the reaction mixture is stirred overnight at RT. Water is added and the resulting mixture is extracted with DCM. The organic layer is dried over anhydrous MgSO4, filtered and concentrated in vacuo to obtain t-butyl 4-(2,4-difluorobenzoyl)piperazine-1-carboxylate as a yellow oil: 1H NMR (CDCl3, 400 MHz) δ 1.47 (s, 9H), 3.30 (m, 2H), 3.41 (m, 2H), 3.53 (m, 2H), 3.76 (m, 2H), 6.86 (dt, 1H, J=8.8 Hz and 0.8 Hz), 6.97 (dt, 1H, J=8.8 Hz and 0.8 Hz), 7.41 (dd, 1H, J=14.4 Hz and 7.2 Hz).

Workup

  1. stirringthe reaction mixture is stirred overnight at RT
  2. extractionthe resulting mixture is extracted with DCM
  3. dry with materialThe organic layer is dried over anhydrous MgSO4
  4. filtrationfiltered
  5. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-679f271b197c495091710f823684a374
Source dataset
uspto-grants-2010_05
Patent number
US07723343B2

Linked notes

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