*3.3. Benzylation of Tertiary Amines—General Procedure 2 (GP2)*

To a stirred mixture of tertiary amine **3** or **4** and K2CO3 (1.1 equivalents) in anhydrous DMF was added benzyl bromide (1.1 equivalents). The resulting reaction mixture was stirred at 25 ◦C for 24 h. DMF was evaporated in vacuo and the residue was purified by column chromatography (CC). The fractions containing product **5** or **6** were combined and the volatiles were evaporated in vacuo.

3.3.1. *N*-Benzyl-1-{(1*S*,2*S*,4*R*)-2-[(tert-butoxycarbonyl)amino]-7,7-dimethylbicyclo[2.2.1] heptan-1-yl}-*N*,*N*-dimethylmethanaminium Bromide (**5a**)

Following *GP2*. Prepared from compound **3a** (1.06 mmol, 315 mg) and benzyl bromide (1.16 mmol, 139 μL), K2CO3 (1.16 mmol, 160 mg), DMF (5 mL), 25 ◦C, 24 h. Isolation by column chromatography (Silica gel 60, EtOAc/MeOH = 4:1). Yield: 340 mg (0.73 mmol, 69%) of colorless oil. [α] r.t.D = +14.0 (0.087, MeOH). EI-HRMS: *m*/*z* = 387.3003 (M)+; C24H39N2O2 requires: *m*/*z* = 387.3006 (M)+; νmax 3369, 3197, 2951, 2199, 2163, 2098, 1989, 1685, 1540, 1490, 1477, 1454, 1392, 1379, 1366, 1299, 1284, 1271, 1252, 1217, 1158, 1125, 1065, 1042, 1012, 947, 917, 882, 868, 854, 839, 783, 752, 732, 706 cm<sup>−</sup>1. 1H-NMR (500 MHz, CDCl3): δ 0.87–0.93 (m, 1H), 0.94 (s, 3H), 0.98 (s, 3H), 1.29–1.34 (m, 1H), 1.36 (s, 9H), 1.58 (t, *J* = 4.4, 1H), 1.86 (br t, *J* = 11.7, 1H), 1.93–2.03 (m, 1H), 2.21 (br t, *J* = 13.1, 1H), 2.47 (d, *J* = 11.7, 1H), 3.17 (s, 3H), 3.25 (s, 3H), 3.44 (br d, *J* = 13.6, 1H), 4.11 (br d, *J* = 13.5, 1H), 4.18 (br t, *J* = 9.9, 1H), 4.97 (d, *J* = 12.3, 1H), 5.03 (br s, 1H), 5.20 (d, *J* = 12.2, 1H), 7.32–7.43 (m, 3H), 7.61 (d, *J* = 7.4, 2H). 13C-NMR (126 MHz, CDCl3): δ 19.48, 20.76, 27.34, 28.28, 28.75, 40.19, 43.67, 50.40, 51.55, 53.72, 54.15, 69.24, 70.42, 80.67, 127.78, 128.94, 130.51, 133.47, 156.14.
