Triphenylphosphine → 6-[1-(tert-butoxycarbonyl)piperidin-4-yl]methoxy-4-[(4-fluoro-1H-indol-5-yl)oxy]-7-methoxyquinazoline

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-[(4-fluoro-1H-indol-5-yl)oxy]-6-hydroxy-7-methoxyquinazoline (250 mg, 0.77 mmol), (prepared as described for the starting material in Example 10), tert-butyl 4-(hydroxymethyl)piperidine-1-carboxylate (199 mg, 0.92 mmol), (prepared as described for the starting material in Example 11), and triphenylphosphine (242 mg, 0.92 mmol) in dichloromethane (15 ml) was stirred and cooled to 0° C. Diisopropyl azodicarboxylate (182 μl, 0.92 mmol) in dichloromethane (2 ml) was added. The mixture was stirred for 3 hours and then a further 0.5 mole equivalent of tert-butyl 4-(hydroxymethyl)piperidine-1-carboxylate, triphenylphosphine and diisopropyl azodicarboxylate added. The mixture was stirred for 1 hour and then concentrated under reduced pressure. The residue was purified by column chromatography eluting with ethyl acetate/hexane (1/1) followed by methylene chloride/methanol (99/1) to give 6-[1-(tert-butoxycarbonyl)piperidin-4-yl]methoxy-4-[(4-fluoro-1H-indol-5-yl)oxy]-7-methoxyquinazoline (306 mg containing 10% w/w triphenylphosphine oxide) which was used without further purification in the next step.

Provenance & Evidence