*3.4. Boc Deprotection of Amines—General Procedure 3 (GP3)*

To a solution of amine **5** or **6** in anhydrous CH2Cl2 (2.5 mL/mmol) was added trifluoroacetic acid (2.5 mL/mmol). The resulting reaction mixture was stirred at 25 ◦C for 2 h. Dichloromethane and trifluoroacetic acid were evaporated in vacuo and the residue was dissolved in CH2Cl2 (2.5 mL/mmol). The organic phase was washed with NaOH (aq., 2 M, 2 × 2.5 mL/mmol) and NaCl (aq. sat., 1 × 2.5 mL/mmol). The volatiles were evaporated in vacuo to give product **7** or **8**.

3.4.1. (1*S*,2*S*,4*R*)-1-[(Benzyldimethylammonio)methyl]-7,7-dimethylbicyclo[2.2.1]heptan-2-aminium 2,2,2-Trifluoroacetate (**7a**)

Following *GP3*. Prepared from compound **5a** (2.1 mmol, 1 g), trifluoroacetic acid (5 mL), CH2Cl2 (5 mL), 25 ◦C, 2 h. Volatile components were evaporated in vacuo, and the residue was dissolved in dichloromethane and washed with NaOH (aq., 2 M) and NaCl (aq. sat.). Yield: 605 mg (1.51 mmol, 72%) of colorless solid, mp = 179.9–182.1 ◦C. [α] r.t.D = +16.2 (0.125, MeOH). EI-HRMS: *m*/*z* = 287.2483 (M)+; C19H31N2 <sup>+</sup> requires: *m*/*z* = 287.2482 (M)+; νmax 3377, 3292, 3042, 2943, 2881, 1685, 1585, 1479, 1457, 1401, 1372, 1302, 1196, 1157, 1113, 1048, 1025, 1010, 989, 935, 917, 881, 854, 819, 780, 785, 753, 733, 716, 707, 632, 607 cm−1. 1H-NMR (500 MHz, CDCl3): δ 0.89 (dd, *J* = 3.4, 13.1, 1H); 0.93 (s, 3H); 0.97 (s, 3H); 1.31–1.38 (m, 1H); 1.61 (t, *J* = 4.6, 1H); 1.77–1.84 (m, 1H); 1.86–1.96 (m, 1H); 2.05–2.13 (m, 1H); 2.44–2.53 (m, 1H); 3.28 (s, 3H); 3.37 (s, 3H); 3.43–3.49 (m, 1H); 3.68 (d, *J* = 13.9, 1H); 3.72 (d, *J* = 13.9, 1H); 4.97 (d, *J* = 12.4, 1H); 5.11 (d, *J* = 12.3, 1H); 7.40–7.48 (m, 3H); 7.56–7.60 (m, 2H), signal for NH2 is missing. 13C-NMR (126 MHz, CDCl3): δ 19.41, 20.51, 26.70, 29.29, 44.19, 44.63, 49.97, 50.49, 52.44, 53.20, 53.69, 69.11, 71.98, 117.64 (q, *J* = 297.3), 128.29, 129.14, 130.57, 133.49, 161.16 (q, *J* = 32.7).

3.4.2. (1*S*,2*R*,4*R*)-1-[(Benzyldimethylammonio)methyl]-7,7-dimethylbicyclo[2.2.1]heptan-2-aminium 2,2,2-Trifluoroacetate (**8a**)

Following *GP3*. Prepared from compound **6a** (1.92 mmol, 900 mg), trifluoroacetic acid (5 mL), CH2Cl2 (5 mL), 25 ◦C, 2 h. Volatile components were evaporated in vacuo, and the residue was dissolved in dichloromethane and washed with NaOH (aq., 2 M) and NaCl (aq. sat.). Yield: 567 mg (1.41 mmol, 74%) of colorless solid, mp = 157.1–158.8 ◦C. [α] r.t.D <sup>=</sup> −9.8 (0.11, MeOH). EI-HRMS: *m*/*z* = 287.2477 (M)+; C19H31N2 <sup>+</sup> requires: *m*/*z* = 287.2482 (M)+; νmax 2953, 2883, 1684, 1476, 1456, 1393, 1371, 1311, 1196, 1153, 1113, 1035, 1009, 936, 911, 851, 820, 798, 784, 735, 714, 631 cm−1. 1H-NMR (600 MHz, CDCl3): δ 0.86 (s, 3H), 0.90 (s, 3H), 1.15–1.22 (m, 1H), 1.34–1.41 (m, 1H), 1.50–1.55 (m, 1H), 1.67 (s, 1H), 1.77 (d, *J* = 13.9, 3H), 1.92 (dd, *J* = 13.0, 7.3, 2H), 3.01 (dd, *J* = 9.0, 4.9, 1H), 3.19 (s, 6H), 3.33 (d, *J* = 13.5, 1H), 4.14 (d, *J* = 13.5, 1H), 4.75 (d, *J* = 12.5, 1H), 4.86 (d, *J* = 12.8, 1H), 7.35–7.41 (m, 3H), 7.56 (d, *J* = 7.4, 2H). 13C-NMR (126 MHz, CDCl3): δ 20.58, 21.40, 27.73, 32.27, 44.01, 44.29, 50.60, 51.35, 51.53, 52.44, 57.11, 64.64, 71.26, 117.56 (q, *J* = 296.8), 127.79, 129.26, 130.81, 133.53, 161.25 (q, *J* = 32.7).

3.4.3. Synthesis of 1-{[(1*S*,2*S*,4*R*)-2-Ammonio-7,7-dimethylbicyclo[2.2.1]heptan-1 yl]methyl}-1-benzylpyrrolidin-1-ium Iodide (**7b**)

Compound **5b** (0.55 mmol, 270 mg) was dissolved in anhydrous CH2Cl2 (8 mL), and then HI (aq., 48%, 5 equivalents, 2.75 mmol, 495 μL) was added. The reaction mixture was stirred for 4 h at 25 ◦C. Volatile components were evaporated in vacuo, and the residue was dissolved in dichloromethane (5 mL) and washed with NaOH (aq., 2 M, 2 × 5mL) and NaCl (aq. sat., 1 × 5mL). Yield: 150 mg (0.34 mmol, 62%) of yellowish semisolid. [α] r.t.D = +18.8 (0.15, MeOH). EI-HRMS: *m*/*z* = 313.2635 (M)+; C21H33N2 <sup>+</sup> requires: *m*/*z* = 313.2635 (M)+; νmax 3273, 2951, 2881, 2188, 2152, 1969, 1594, 1458, 1372, 1303, 1217, 1142, 1077, 1033, 1004, 917, 822, 764, 725, 641 cm<sup>−</sup>1. 1H-NMR (600 MHz, CDCl3): δ 1.03–1.06 (m, 1H), 1.06 (s, 3H), 1.07 (s, 3H), 1.41–1.50 (m, 1H), 1.67 (t, *J* = 4.6, 1H), 1.77 (td, *J* = 10.7, 9.7, 6.5, 1H), 1.81–1.88 (m, 1H), 1.92–1.99 (m, 1H), 2.05–2.11 (m, 1H), 2.12–2.21 (m, 2H), 2.26 (ddd, *J* = 13.4, 9.4, 4.1, 1H), 2.36–2.75 (m, 3H), 3.68 (dt, *J* = 10.5, 3.1, 1H), 3.75 (ddd, *J* = 12.3, 8.5, 5.9, 1H), 3.81–3.87 (m, 1H), 3.83 (d, *J* = 14.1, 1H), 3.89 (d, *J* = 14.2, 1H), 4.07 (ddd, *J* = 12.2, 8.3, 6.3, 1H), 4.16 (ddd, *J* = 11.9, 8.2, 6.2, 1H), 5.06 (d, *J* = 12.6, 1H), 5.25 (d, *J* = 12.6, 1H), 7.42–7.50 (m, 3H), 7.66 (d, *J* = 6.6, 2H). 13C-NMR (151 MHz, CDCl3): δ 19.88, 21.16, 21.96, 22.08, 26.80, 29.23, 42.76, 44.69, 52.63, 53.69, 54.48, 60.85, 61.96, 63.75, 67.23, 128.66, 129.39, 130.71, 133.42.
