Trifluoroacetic acid → 4-[(2-ethoxymethyl-1H-imidazo[4,5-c]quinolin-1-yl)methyl]piperidin-4-ol

Participants

Reaction Steps

Under a nitrogen atmosphere a mixture of trifluoroacetic acid (40 mL) and dichloromethane (200 mL) was chilled in an ice bath. A solution of tert-butyl 4-[(2-ethoxymethyl-1H-imidazo[4,5-c]quinolin-1-yl)methyl]-4-hydroxypiperidine-1-carboxylate (20 g, Example 4 Parts A through E) in dichloromethane (200 mL) was slowly added. The reaction mixture was allowed to warm to ambient temperature, stirred for 6 hours, and then concentrated under reduced pressure to provide a dark amber oil. The oil was dissolved in water (200 mL), the pH was adjusted to 13 with 50% sodium hydroxide, and the mixture was extracted with dichloromethane. The combined extracts were dried over magnesium sulfate, filtered, and concentrated under reduced pressure to provide 15.2 g of 4-[(2-ethoxymethyl-1H-imidazo[4,5-c]quinolin-1-yl)methyl]piperidin-4-ol as a tan frothy solid.

Provenance & Evidence