Potassium Carbonate → Tert-butyl 4-(3-methoxy-4-nitrophenyl)piperazine-1-carboxylate

HRID 2272392Notes

Reaction equation

F[C:2]1[CH:3]=[CH:4][C:5]([N+:10]([O-:12])=[O:11])=[C:6]([O:8][CH3:9])[CH:7]=1.[N:13]1([C:19]([O:21][C:22]([CH3:25])([CH3:24])[CH3:23])=[O:20])[CH2:18][CH2:17][NH:16][CH2:15][CH2:14]1.C(=O)([O-])[O-].[K+].[K+]>CS(C)=O.O>[CH3:9][O:8][C:6]1[CH:7]=[C:2]([N:16]2[CH2:15][CH2:14][N:13]([C:19]([O:21][C:22]([CH3:25])([CH3:24])[CH3:23])=[O:20])[CH2:18][CH2:17]2)[CH:3]=[CH:4][C:5]=1[N+:10]([O-:12])=[O:11]

Participants

Conditions

Temperature: 90 °C

Procedure

A mixture of 5-fluoro-2-nitroanisole (3.00 g, 17.5 mmol), tert-butyl piperazine-1-carboxylate (4.57 g, 24.5 mmol) and potassium carbonate (3.63 g, 26.3 mmol) in dimethyl sulfoxide (20 mL) was heated at 90° C. for 1.5 hours under a nitrogen atmosphere. The reaction mixture was cooled and diluted with water (100 mL). The resulting precipitate was filtered and dried to give a bright yellow solid. The solid was suspended in a 5:1 solution of petroleum ether/diethyl ether (50 mL), sonicated for 2 minutes, filtered and dried to give the title compound (I1) (3.95 g, 66%) as a bright yellow solid; 1H NMR (300 MHz, d6-DMSO) δ 1.42 (s, 9 H), 3.46 (brs, 8 H), 3.90 (s, 3 H), 6.52 (s, 1 H), 6.57 (d, 1 H, J=9.5 Hz) and 7.89 (d, 1 H, J=9.3 Hz). LCMS Method B: rt 7.45 min; m/z 338.2 [M+H]+.

Workup

temperatureThe reaction mixture was cooled
filtrationThe resulting precipitate was filtered
customdried
customto give a bright yellow solid
customsonicated for 2 minutes
filtrationfiltered
customdried

Sources & evidence

ORD record: ord-aeecf3b60f22411d878d7efd0a08251d
Source dataset: uspto-grants-2015_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09120761B2

Reaction notes

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