*4.5. N,N'-Ditosyl-1,3-propanediamine (5)*

Tosyl chloride (40.0 g, 210 mmol) was molten in a beaker at 80 ◦C and 1,3-propanediamine (3, 8.9 mL, 106 mmol) was added dropwise; to complete the reaction, the mixture was stirred for an additional 30 min at 80 ◦C. After cooling to 20 ◦C, aq. HCl (2 M) was added, and the precipitate was washed with water followed by a recrystallization from ethanol to furnish **5** (33.7 g, 83%) as a colorless solid; m.p. 138 ◦C (lit: [49] 137–140 ◦C); Rf = 0.75 (silica gel, hexanes/ethyl acetate, 4:6); UV-Vis (CHCl3): λmax (log ε) = 228 nm (4.16); IR (ATR): *ν* = 3271*w*, 1595*w*, 1431*w*, 1305*s*, 1214*w*, 1154*s*, 1088*m*, 1024*w*, 980*m*, 858*m*, 815*s*, 698*s*, 550*s*, 568*s*, 489*m* cm<sup>−</sup>1; 1H NMR (400 MHz, CDCl3): δ = 7.73 (*m*, 4H, 4-H, 8-H), 7.32–7.25 (*m*, 4H, 5-H, 7-H), 3.02 (*t*, *J* = 5.8 Hz, 4H, 2-H), 2.42 (*s*, 6H, 9-H), 1.67 (*p*, *J* = 6.2 Hz, 2H, 1-H) ppm; 13C NMR (101 MHz, CDCl3): δ = 143.6 (C-6), 136.8 (C-3), 129.8 (C-5, C-7), 127.0 (C-4, C-8), 39.8 (C-2), 29.9 (C-1), 21.5 (C-9) ppm; MS (ESI, MeOH/CHCl3, 4:1): *m*/*z* = 405.0 (100%, [M+Na]+).

#### *4.6. 1,3-Propanediol Ditosylate (6)*

A mixture of 1,3-propanediol (**4,** 16.0 g, 210 mmol) and tosyl chloride (88.0 g, 461 mmol) in dry pyridine (70 mL) was stirred at 0 ◦C for 1 h. The product was precipitated by adding aq. HCl (2 M), filtered off and dried. Compound **6** (69.9 g, 87%) was obtained as a colorless solid; m.p. 92 ◦C (lit.: [51] 92–93 ◦C); Rf = 0.49 (hexanes/ethyl acetate, 6:4); UV-Vis (CHCl3): λmax (log ε) = 225 nm (4.11); IR (ATR): *ν* = 2978*w*, 1599*m*, 1496*w*, 1470*w*, 1421*w*, 1352*s*, 1293*m*, 1254*w*, 1190*m*, 1172*s*, 1095*m*, 1029*m*, 1021*m*, 941*s*, 892*w,* 852*s*, 810*s*, 739*s*, 660*s*, 580*s*, 568*s*, 549*s,* 488*m* cm−1; 1H NMR (400 MHz, CDCl3): δ = 7.75–7.23 (*m*, 8H, 4-H, 5-H, 7-H, 8-H), 4.06 (*t*, *J* = 6.0 Hz, 4H, 2-H), 2.46 (s, 6H, 9-H), 1.99 (*p*, *J =* 6.0 Hz, 2H, 1-H) ppm; 13C NMR (101 MHz, CDCl3): δ = 145.1 (C-6), 132.6 (C-3), 130.0 (C-5, C-7), 127.9 (C-4, C-8), 65.9 (C-2), 28.7 (C-1), 21.6 (C-9) ppm; MS (ESI, MeOH/CHCl3, 4:1): *m*/*z* = 407.3 (100%, [M+Na]+).
