for the following products
1-Benzyl-3-methoxycarbonyl-4-piperidone hydrochloride | Methyl 1-benzyl-4-oxopiperidine-3-carboxylate hydrochloride | N-Benzyl-3-carbomethoxy-4-piperidone hydrochloride and Methyl 1-benzyl-4-oxo-3-piperidinecarboxylate hydrochloride