To a solution of triphenylphosphine (2 eq) in THF was added di-terbutylazodicarboxylate (2 eq). The mixture was stirred 15 minutes at ambient temperature under nitrogen atmosphere. To that was added tert-butyl-4-hydroxypiperidine-1-carboxylate (5 eq). The mixture was stirred 15 minutes at ambient temperature followed by addition of 2-(ethylthio) quinazolin-7-ol (1 eq). The mixture was stirred overnight at ambient temperature. The reaction mixture was concentrated and purified by flash column chromatography (10% EtOAc/Hexane) to provide product as a white solid in 90% yield. ES/MS m/z 390.1 (MH+).
