Structures of 1h-indole-3-ethylene-3'-methoxysalicylaldimine (3'-meo-saltpa) and 3-[3'-azapentyl-3'-en-4'-(2''-hydroxyphenyl)]indole (ohaph-tpa)

3'-Meo-salTPA, systematic name 2-[2-(1Hindol-3-yl)ethyliminomethyl]-6-methoxyphenol, ClsH18N202, M r = 294.34, triclinic, P i , a = 11.932(2), b = 1 1 . 5 9 0 ( 3 ) , c = 1 1 . 4 0 1 ( 4 ) A , a = 89.94(2), f l= 101.44 (2), ),= 101.24 (2) ° , , V = 1514(1)A 3, Z = 4 , D x = l . 2 9 , D m = l ' 3 0 M g m :-3, F(000) = 624, 2(Mo Kt~) = 0.71069 A, /a = 0.92 mm -l, room temperature, final R = 0.0505, wR = 0.0597 for 1809 observed reflections. OHAPH-TPA, systematic name 2-{1-[2-(1H-indol-3-yl)ethylimino]ethyl}phenol, CIsH~sN20, M r = 278.36, monoclinic, * Author to whom correspondence should be addressed. 0108-2701/88/040678-04503.00 P2~/a, a = 10.018 (2), b = 14.669 (4), c = 10.015 (2) A, f l= 90.54 (2) °, V = 1472 (1) A3, Z = 4, D x = 1.26, D m = 1.29 Mg m -3, F(000) = 592, ~ . (MoKa)=0 .71069A, # = 0 4 4 m m -l, final R = 0.0962, wR = 0 ' 1 1 7 4 for 1490 observed reflections. The two structures are compared and some structural features are emphasized. The C7A-C8A bond length for both compounds is shorter than a normal aromatic C C bond. Both structures also show intramolecular and intermolecular hydrogen bonds, the first between the phenolic H and the N of the imino group and the second between the indolic N--H and the phenolic O of