TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Compound: The pi -conjugated cyclic compound of formula (7) is halogen-containing tetra-benzo porphyrin of formula (7a). The halogen-containing tetra-benzo porphyrin of formula (7a) is halogen-containing tetra-benzo porphyrin complex of formula (8).X,Y',m,n=same as defined above;andM=metal or semimetal ion.Preferred Methods: The halogen-containing isoindole of formula (2) is formylated, to obtain isoindole (first intermediate) of formula (6b). The halogen-containing isoindole (2) and dialkyl formamide are reacted in presence of halogenated phosphoryl, to obtain isoindole (first intermediate) of formula (6b). The isoindole (6b) is reduced, to obtain hydroxymethylated-2H-isoindole of formula (6c). The halogen-containing isoindole (2) is amino-methylated, to obtain isoindone-containing compound (second intermediate) of formula (6a). The isoindone-containing compound (second intermediate) is hydrolyzed, to obtain isoindole (first intermediate). The halogen-containing isoindole (2) and halogenated methylene dialkyl ammonium are reacted and oxidized using an oxidizing agent, to obtain halogen-containing tetra-benzo porphyrin of formula (7a). A phthalonitrile of formula (1) is reduced with hydride reducing reagent such as aluminum hydride, its complex, boron hydride or its complex, by catalytic-hydrogenation method and mixed with a proton acid or alkali, to obtain halogen-containing isoindole (2).X,Y',n,m=same as defined above;andR7,R8=1-4C alkyl.    TECHNOLOGY FOCUS - POLYMERS - Preferred Methods: The halogen-containing isoindole (2) is oxidized and polymerized, to obtain polymer which has isoindole-containing repeating unit of formula (4). N-substituted isoindole of formula (3) is manufactured using the halogen-containing isoindole (2). The N-substituted isoindole of formula (3) is oxidized and polymerized, to obtain polymer which has isoindole-containing repeating unit of formula (5). A phthalonitrile of formula (9) is subjected to catalytic hydrogenation in presence of an acid, to obtain polymer which has isoindole-containing repeating unit of formula (10).X,Y'=same as defined above;R4=alkyl, aryl, alkylaryl or acyl;D=halogen atom;andp=0-4. EXAMPLE - Tetrafluoro phthalonitrile (in g) (3) and spin-dehydrated toluene (75 ml) were mixed under nitrogen atmosphere in a reaction container. Then, 0.99 M toluene solution (61 ml) of diisobutyl aluminum hydride was dripped into reaction mixture which was cooled in an ice bath, and 2 M hydrochloric acid (45 ml) was added. The reaction mixture was then extracted with ethyl acetate, neutralized with sodium hydrogen carbonate solution, washed by saturated salt solution and spin-dehydrated by anhydrous sodium sulfate. The obtained extract was concentrated and purified by silica-gel column chromatography, to obtain 4,5,6,7-tetrafluoro-2H-isoindole (0.64) with yield of 22.6%.