ABSTRACT: The 7-nitro-2'-phenyl-5',6',7',7a'-tetrahydrospiro[indeno[1,2-b]quinoxaline-11,3'-pyrrolizine]-1',1'(2'H)-dicarbonitrile (SIQPI), 2'-(4-cyanophenyl)-7-nitro-5',6',7',7a'-tetrahydrospiro[indeno[1,2-b]quinoxaline-11,3'-pyrrolizine]-1',1'(2'H) dicarbonitrile (SIQPII), and 2'-(4-methoxyphenyl)-7-nitro-5',6',7',7a'-tetrahydrospiro[indeno[1,2-b]quinoxaline-11,3'-pyrrolizine]-1',1'(2'H)-dicarbonitrile (SIQPIII) were used to photocatalyze quinonoid phenolphthalein (QHIn) in aq-ACN-EtOH (mixed solvent) with NaCl and KCl electrolytes. SIQPI, II, and III spiroindenoquinoxaline pyrrolidines (SIQPs) as spiroheterocyclic photocatalysts alone could not reduce QHIn, but with the addition of electrolytes they are reduced via π cationic interactions (PCI). SIQPI, II
