Cesium carbonate → HCID 22396597, compound

Participants

Reaction Conditions

Reaction Steps

In a 20 mL vial a solution of MeOH/dioxane (10%, 1.5 mL, degassed with N2) was added to a mixture of 3-(tert-butyloxycarbonyl)-9-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,2,3,4,5,6-hexahydroazepino[4,5-b]indole (0.097 g, 0.235 mmol), cesium carbonate (0.115 g, 0.35 mmol), and 4-bromopyridine hydrochloride (0.137 g, 0.70 mmol) and diphenylphosphinoferrocene (0.07 g, 5 mol %) were added. The mixture was flushed with argon and tris(dibenzylideneacetone)dipalladium (0) (0.06 g, 3 mol %) was added and the vial was placed on a shaker heated at 90° C. for 18 h. Equivalent amounts of cesium carbonate and the palladium catalyst were added with a small amount of MeOH for solubility, and the vial was returned to the shaker and heated at 90° C. for 48 h. MeOH and Bio-Rad Ag. 50W-X2 resin (0.8 g, 5.2 meq, 18 equivalents) were added and heated on the shaker at 65° C. for 2 h. The mixture was rinsed into a fritted plastic syringe and was washed with: MeOH, water, 2 N pyridine in MeOH, THF, MeOH, THF and finally CH2Cl2. The resulting cake of resin was then washed with 4 M NH4OH/MeOH and THF successively into tared vials, which were concentrated down on a Genevac for 18 h. The product was purified on a reverse phase HPLC system to give 4.3 mg (7%) of the title compound as the formate salt. MS (EI) m/z 264 (MH+).

Provenance & Evidence