Reaction #157357

Reaction equation

dichloromethane

tert-butyl 4-(2-chlorooxazole-4-carbonyl)-3-((pyridin-3-yloxy)methyl)piperazine-1-carboxylate

benzeneboronic acid

sodium carbonate

→

tert-butyl 4-(2-phenyloxazole-4-carbonyl)-3-((pyridin-3-yloxy)methyl)piperazine-1-carboxylate

Solvents

toluene

1,4-dioxane

water

Conditions

Workup

1. 1
   TemperatureUpon cooling to room temperature
2. 2
   Filtrationthe reaction mixture was filtered through Celite®
3. 3
   Concentrationconcentrated under reduced pressure
4. 4
   Otherpurified by HPLC (10 to 90% MeCN/0.1% TFA in H2O/0.1% TFA gradient)

Procedure

[1,1′-bis(diphenylphosphino)ferrocene]-dichloropalladium(II) complex with dichloromethane (1:1) (6.7 mg, 0.0082 mmol) was added to a mixture of tert-butyl 4-(2-chlorooxazole-4-carbonyl)-3-((pyridin-3-yloxy)methyl)piperazine-1-carboxylate (69.5 mg, 0.164 mmol), benzeneboronic acid (40 mg, 0.33 mmol) and sodium carbonate (35 mg, 0.33 mmol) in toluene (4 mL), 1,4-dioxane (1 mL), and water (1 mL). The reaction mixture was heated to 80° C. overnight. Upon cooling to room temperature, the reaction mixture was filtered through Celite®, concentrated under reduced pressure, and purified by HPLC (10 to 90% MeCN/0.1% TFA in H2O/0.1% TFA gradient). This gave 44.8 mg (47%) of the TFA salt of the desired product. LC-MS: RT=8.49 min, [M+H]+=465.0.

Source