Azobisisobutyronitrile → 6-(2-Chlorophenyl)-5-(4-chlorophenyl)-2-(2,2-dimethylpropanoyl)furo[2,3-b]pyridine-3-carbaldehyde

Beteiligte Stoffe

Reaktionsschritte

A 10 mL rb flask equipped with a magnetic stir bar was charged with 0.227 g (0.52 mmol) of the product of Example 89, 0.101 g (0.57 mmol) of N-bromosuccinimide, 3 mL CCl4 and ca. 5 mg of 2,2′-azobisisobutyronitrile (AIBN). The reaction mixture was heated to reflux under a nitrogen atmosphere for 2 h then cooled to room temperature and filtered. The filtrate was evaporated in vacuo, and the residue was then redissolved in 2 mL of DMSO. The solution containing the crude bromination product was transferred to a 10 mL reaction tube of a CEM Corporation Discover 300 Watt microwave reactor and 73 mg (0.62 mmol) of N-methylmorpholine-N-oxide was added. The reaction vessel was sealed, placed in the microwave reactor and heated at 150° C. for 2–3 min. After the reaction mixture had cooled to room temperature, it was partitioned between EtOAc and 10% aq. NaHSO4 and extracted. The organic layer was washed with 10% aq. NaHSO4, water, brine, dried (MgSO4), filtered and evaporated. The residue was purified on a silica gel flash chromatography column eluted with 0–10% EtOAc-hexane. Evaporation of the purified fractions and drying in vacuo afforded the title compound. HPLC/MS: 452.1 (M+1), 454.0 (M+3); Rt=4.63 min.

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