Reagents
and conditions: (a)
1-benzylpiperidin-4-amine, DMF, r.t.; (b) 3-chloro-2-(chloromethyl)prop-1-ene,
NaH, THF; (c) hydroxylamine hydrochloride, Et3N, EtOH;
(d) Raney nickel, H2, 30–50 psi, r.t.; (e) for 6 (y = 1), tert-butyl 4-(aminomethyl)piperidine-1-carboxylate,
DMF, r.t.; (f) for 7 (y = 2), tert-butyl 4-(2-aminoethyl)piperidine-1-carboxylate, DMF,
r.t.; (g) TFA; (h) benzyl bromide, Et3N, DMF, r.t.