Sodium Carbonate → tert-Butyl 4-(5-(2-methoxy-4-(1H-pyrazol-1-yl)phenyl)-1,3,4-thiadiazol-2-yl)piperazine-1-carboxylate

HRID 579324Notes

Reaction equation

HRID 579324 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]([N:18]2[CH:22]=[CH:21][CH:20]=[N:19]2)[CH:6]=[CH:7][C:8]=1B1OC(C)(C)C(C)(C)O1.Br[C:24]1[S:28][C:27]([N:29]2[CH2:34][CH2:33][N:32]([C:35]([O:37][C:38]([CH3:41])([CH3:40])[CH3:39])=[O:36])[CH2:31][CH2:30]2)=[N:26][N:25]=1.C([O-])([O-])=O.[Na+].[Na+]>O1CCOCC1.O.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[CH3:1][O:2][C:3]1[CH:4]=[C:5]([N:18]2[CH:22]=[CH:21][CH:20]=[N:19]2)[CH:6]=[CH:7][C:8]=1[C:24]1[S:28][C:27]([N:29]2[CH2:30][CH2:31][N:32]([C:35]([O:37][C:38]([CH3:41])([CH3:40])[CH3:39])=[O:36])[CH2:33][CH2:34]2)=[N:26][N:25]=1

Participants

7

Reactant 3

HCID 10340Sodium CarbonateHCID 66545097tert-Butyl 4-(5-bromo-1,3,4-thiadiazol-2-yl)piperazine-1-carboxylateHCID 867105591-(3-methoxy-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-1H-pyrazole2×

Product 1

HCID 86727145tert-Butyl 4-(5-(2-methoxy-4-(1H-pyrazol-1-yl)phenyl)-1,3,4-thiadiazol-2-yl)piperazine-1-carboxylateYield 78%

Reagents, catalysts & solvents 3

HCID 178418397HCID 178418397, compoundCatalystHCID 962WaterSolventHCID 312751,4-DioxaneSolvent

Conditions

Temperature
120 °C

Procedure

To a stirred suspension of 1-(3-methoxy-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-1H-pyrazole [Intermediate 1] (132 mg, 0.441 mmol) and tert-butyl 4-(5-bromo-1,3,4-thiadiazol-2-yl)piperazine-1-carboxylate (140 mg, 0.401 mmol) in dioxane (2 mL) was added Pd(PPh3)4 (23 mg, 20 μmol) followed by a solution of Na2CO3 (85 mg, 0.802 mmol) in water (0.5 mL). The reaction mixture was purged with nitrogen, sealed, and heated at 120° C. for 30 minutes under microwave irradiation. The reaction mixture was cooled to room temperature, diluted with DCM (20 mL), washed with water (10 mL), then the organic phase was separated and concentrated in vacuo to afford the crude product as a pale brown solid. The crude material was purified by flash chromatography using a 12 g silica cartridge running an EtOAc/heptane gradient to afford the title compound as a pale yellow/off-white solid (138 mg, 78% yield). LC-MS: Rt 1.34 min; MS m/z 443.3 [M+H]+ [Method A]. 1H NMR (400 MHz, DMSO-d6) δ ppm 8.65 (d, J=2.53 Hz, 1H), 8.21 (d, J=8.59 Hz, 1H), 7.80 (d, J=1.52 Hz, 1H), 7.66 (d, J=2.02 Hz, 1H), 7.60 (dd, J=8.59, 2.02 Hz, 1H), 6.59-6.62 (m, 1H), 4.05 (s, 3H), 3.51 (s, 8H), 1.43 (s, 9H).

Workup

  1. customThe reaction mixture was purged with nitrogen
  2. customsealed
  3. temperatureThe reaction mixture was cooled to room temperature
  4. additiondiluted with DCM (20 mL)
  5. washwashed with water (10 mL)
  6. customthe organic phase was separated
  7. concentrationconcentrated in vacuo
  8. customto afford the crude product as a pale brown solid
  9. customThe crude material was purified by flash chromatography

Sources & evidence

ORD record
ord-83c56f95eab6477bad096092269ba51e
Source dataset
uspto-grants-2015_05
Patent number
US09040712B2

Reaction notes

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