Treat a solution of (4-hydroxy-piperidin-1-yl)-acetic acid methyl ester (10.0 g, 57.7 mmol) and imidazole (4.71 g, 69.2 mmol) in DMF (100 mL) with t-butyl-diphenylsilyl chloride (19.04 g, 69.3 mmol) and stir for 16 hours at room temperature. Dilute the reaction with diethyl ether and wash with water. Dry the organic layer (Na2SO4), remove the solvent in vacuo to afford crude product, and purify with a 2% methanol in CH2Cl2 to afford 17.38 g (73%) of the titled product. Rf=0.71 (9/1 CH2Cl2/methanol). ES MS (m/z): 412 (M+).
