Methyl 1-benzyl-4-oxopiperidine-3-carboxylate hydrochloride → 6-Benzyl-4-chloro-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-2-amine
Reaction equation
[ClH:1].[CH2:2]([N:9]1[CH2:14][CH2:13][C:12](=O)[CH:11]([C:16](OC)=O)[CH2:10]1)[C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1.C(=O)(O)O.[NH2:24][C:25]([NH2:27])=[NH:26]>CCO>[CH2:2]([N:9]1[CH2:14][CH2:13][C:12]2[N:26]=[C:25]([NH2:27])[N:24]=[C:16]([Cl:1])[C:11]=2[CH2:10]1)[C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1Participants
4
Procedure
To EtOH (16 mL) cooled to 0° C. (ice/H2O bath) was added Na spheres (204 mg, 8.9 mmol). The mixture was stirred until all Na dissolved. Methyl 1-benzyl-4-oxo-3-piperidine-carboxylate hydrochloride (3.0 g, 10.1 mmol) and guanidine carbonate (1.4 g, 7.6 mmol) were added. The mixture was refluxed for 16 h. After the reaction was cooled to room temperature, the solid was collected by filtration, washed with EtOH, and dried under vacuum. Desired compound (2.58 g, 10.0 mmol; 99+% yield); mp=202-212° (dec.); ES MS [M+H]+=257; TLC (CH2Cl2—MeOH, 90:10); Rf=0.20. Step 2. Preparation of 6-benzyl-4-chloro-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-2-amine.