NITROGEN CONFIGURATION DETERMINED BY X-RAY-ANALYSIS ON AN HOMOGENEOUSSERIES OF 3-INDOLINONES

The X-ray diffraction analyses of 2-methyl-2-phenylindolin-3-one 1, 1, 2-dimethyl-2-phenylindolin-3-one 2, 1-hydroxy-2-methyl-2-phenylindolin -3-one 3 and 1-methoxy-2-methyl-2-phenylindolin-3-one 4 have been carr ied out and the structural data were compared with those of 1-oxyl-2-m ethyl-2-phenylindolin-3-one 5. The results demonstrate that only compo unds 2 and 5 show planar trigonal geometry which is coplanar with the conjugated benzene ring of the indolinic nucleus, whereas compounds 3 and 4 show a marked pyramidality of the nitrogen. Even if compound 1 s hows a certain pyramidality of the nitrogen, it has been considered si milar to compound 2. The reactivity of all studied compounds fit the s tructural data.