To a 1 L round bottom flask was added (4-hydroxymethyl-phenyl)-carbamic acid tert-butyl ester (22.3 g, 0.10 mol) obtained from Examples 2pp through 2ooo, Step 1, dichloromethane (400 mL) and triphenylphospine (31.5 g, 0.12 mol). Upon cooling to 0 °C, N-bromosuccinimide (19.6 g, 0.11 mmol) was added in small portions, and the reaction was allowed to warm to room temperature and stirred under nitrogen for 1 h. The mixture was transferred into a large flask, and hexanes were added until the solution became turbid. The solution was eluted through a plug of silica (300 g) with 1:9 ethyl acetate: hexanes and concentrated to yield Tert-Butyl 4-(bromomethyl)phenylcarbamate (12.8 g, 0.057 mol, 57 percent) as a white solid.
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[2] Patent: WO2006/31806, 2006, A2. Location in patent: Page/Page column 99
[3] Journal of Medicinal Chemistry, 1989, vol. 32, # 4, p. 811 - 826