Pyridine → 5-Tert-butyldimethylsilyloxy-2-(phthalimido)-n-[1-(4-pyridyl)piperidin-4-ylcarbonyl]aniline

Beteiligte Stoffe

Reaktionsschritte

1-(4-Pyridyl)piperidine-4-carboxylic acid (176 mg, 0.85 mmol) and thionyl chloride (93 mL, 1.28 mmol) in 5 mL methylene chloride were heated under reflux for 2 h. The mixture was allowed to cool, concentrated in vacuo to a white foam and dried under vacuum. The foam was suspended in dry methylene chloride (5 mL) then added were 5-tert-butyldimethylsilyloxy-2-(phthalimido)aniline (314 mg, 0.85 mmol)(see Example 167, step C, above) as a solution in 5 mL methylene chloride and 1 mL pyridine in several portions. The cloudy mixture was stirred 45 min then passed through a 35×80 mm plug of silica gel eluting first with methylene chloride then with 9:1:0.1 methylene chloride/methanol/-ammonium hydroxide. Appropriate fractions were combined, concentrated in vacuo and dried under vacuum to yield 360 mg (76%) of the desired intermediate phthalimide.

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