Triethylamine → 6-Chloro-3-(2-fluorophenyl)-7-(trimethylsilyl)-[1,2,4]triazolo[4,3-b]pyridazine

Beteiligte Stoffe

Reaktionsschritte

Compound 22 (4.1 g, 12.1 mmol) and 1,2-dibromotetrachloroethane (7.9 g, 24.2 mmol) were suspended in acetonitrile (80 mL) and cooled to less than 5° C. Triphenylphosphine (11 g, 30.2 mmol) was added in small portions allowing the reaction to exotherm slightly but keeping the temperature at about 5-7° C. The solids started to dissolve and then a new precipitate began to form. The thick mixture was stirred cold for 15 min. Triethylamine (10 mL, 72.6 mmol) was added dropwise, again allowing an exotherm but keeping the temperature about 5-7° C. The reaction was stirred in an ice-water bath for 1 hr. The mixture was diluted with dichloromethane (200 mL) and washed with water. The organic layer was dried over Na2SO4 and concentrated to a brown liquid. The material was combined with crude material from another (2.9 mmol) reaction and purified on an Analogix automated column chromatography system (SF25-80 g column, 10-40% EtOAc/heptane) to provide 3.8 g (79%) of 23 as a tan, slightly sticky, solid.

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