Sodium Carbonate → HCID 21947805, compound

Participants

Reaction Steps

A suspension of (4-bromo-3-methylphenyl)-[10,11-dihydro-5H-pyrrolo[2,1-c][1,4]benzodiazepin-10-yl]methanone of Step A (1.14 g, 2.9 mmol), pyridine-4-boronic acid (0.368 mg, 2.9 mmol) and sodium carbonate (0.760 g, 7.2 mmol) in a mixture of toluene (30 mL), water (10 mL), and ethanol (5 mL) was sparged with nitrogen for 15 minutes. To this was added tetrakis(triphenylphosphine)palladium(0) (0.027 g) and the mixture was heated to reflux under a static pressure of nitrogen. After 24 hours additional boronic acid (0.128 mg, 1 mmol) and sodium carbonate (0.116 g) were added and the heating was continued for 24 hours. Additional catalyst (0.012 g) was added and heating was continued for another 24 hours. The mixture was partitioned between ethyl acetate and hexane. The water layer was washed twice with ethyl acetate and the combined organic layers were dried over anhydrous magnesium sulfate and stripped to a solid. Flash chromatography of the residue on silica gel eluting with 30% ethyl acetate in hexane provided 0.379 g of the desired product which was recrystallized from ethyl acetate/hexanes as tan plates, m.p. 208-210° C.

Provenance & Evidence