Dichloromethane → 2,2-dimethyl-1-[2-(3,4,5-trimethoxy-phenyl)-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazin-7-yl]-pent-4-en-1-one

Participants

Reaction Steps

A mixture of impure 1-[2-bromo-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazin-7-yl]-2,2-dimethyl-pent-4-en-1-one (0.900 g, “2.05 mmol), 3,4,5-trimethoxyphenyl boronic acid (0.479 g, 2.26 mmol), potassium carbonate (0.850 g, 6.15 mmol) and Pd(dppf)Cl2.CH2Cl2 (0.171 g, 0.21 mmol) in 15 mL of 1,4-dioxane and 4 mL of water was stirred at 120° C. in a microwave for 1 h. The resulting mixture was partitioned between 300 mL of ethyl acetate and 200 mL of water. The organic layer was dried over MgSO4, filtered and concentrated to a residue. Column chromatography (0→35% EtOAc/hexanes) afforded 0.777 g (29% for three steps from 2-bromo-5H-pyrrolo[2,3-b]pyrazine) of 2,2-dimethyl-1-[2-(3,4,5-trimethoxy-phenyl)-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazin-7-yl]-pent-4-en-1-one.

Provenance & Evidence