A NOVEL REACTION OF 4,7-TRINITRO-9H-FLUOREN-9-YLIDENE)PROPANEDINITRILE WITH N-ARYLISOINDOLINES

N-Arylisoindolines 1a-c reacted with 4,7-trinitro-9H-fluoren-9-ylidene )propanedinitrile (A) in pyridine with admission of air via a net alph a-H-atom abstraction and formation of [3-(2-aryl-3-arylimino-2,3-dihyd ro- oindol-1-ylidene)-2-aryl-2,3-dihydro-1H-isoindol-1 -ylidene]propan edinitriles 2a-c, -3-(2-aryl-3-arylimino-2,3-dihydro-1H-isoindolyl-1 d ene)-2,3-dihydro-1H-isoindol-1-ylidene]arenamines 3a,b, -aryl-1H-isoin dole-1,3(2H)-diylidene]bisarenamines 4a,b and N-arylphthalimides 5a-c in moderate yields. 2,4,7-Trinitro-9-fluorenone as well as one reducti on product each of the latter and of A, namely compounds 6 and 7, resp ectively, are also found. The structure of 2b has been unambiguously c onfirmed by an X-ray crystal structure analysis. A rationale for the c onversions observed is presented. These involve dehydrogenation and ox idative couplings of 1a-c as well as transfer of N-aryl fragment from 1a-c to intermediate products.