A mixture of 2-(1-bromo-ethyl)-3-methyl-3H-quinazolin-4-one (801 mg, 3 mmol), 4-amino-1-N-Boc piperidine (661 mg, 3.3 mmol), potassium iodide (498 mg, 3 mmol) and potassium carbonate (622 mg, 4.5 mmol) in acetonitrile (12 mL) was heated at 65° C. for 3 days. The reaction mixture was then concentrated in vacuo. The residue was dissolved in dichloromethane and washed with saturated sodium thiosulphate solution and water. The organic layer was dried over magnesium sulfate and concentrated in vacuo to yield 4-[1-(3-Methyl-4-oxo-3,4-dihydro-quinazolin-2-yl)-ethylamino]-piperidine-1-carboxylic acid tert-butyl ester (HPLC ret. time 2.20, 10-99% CH3CN, 5 min run, ESI-MS m/z 387.4 (MH+).
