, (dpea) was prepared according to the procedure described in reference [51], with a yield of 1.777 g, 77%. IR data (?cm ?1 ): 3068 w, 3052 w, 3001 w, 2973 w, 2929 w, 2869 w, 1640 w, 1582 s, 1560 m, 1466 s, 1420 s, 1320 m, 1263 s, 1137 m, 1046 w, 984 m, 953 m, 922 w, 769 s, 736 m, 699 w, 637 w, 622 w, 573 m

J. H-h-=-6-;-3-j-h-h-=, Hz); 6.90 (2H, t, 3 J H-H = 6 Hz); 7.08 (2H, d, 3 J H-H = 8.4 Hz), vol.7

, 37 (C=C, aromatic, quat). 2,2'-Dipyridyl-N-propylamine (dppa) was prepared using a similar procedure as reported for 2,2'-dipyridyl-N-ethylamine (dpea), by replacing the ethyl iodide by the propyl iodide, vol.157

, 73%). IR data (?/cm ?1 ): 3420 br, 3068 w, 3052 w, 3007 m, 2961 m, 2872 m, 1640 w, 1582 s, 1558 s, 1529 m, 1465 s, 1419 s, 1377 s, 1321 m, 1276 s, 1236 m, 1142 m, 1106 m, 1050 m, 985 f, 957 m, 938 m, 890 s, 854 w, 768 s, 735 s, 638 w, 619 m, 605 m, 578 m, 531 m, 503 m, 466 w, 433 m. 1 H NMR (400 MHz, vol.3

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