TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Disclosed): Preparation of mono- and di-imide naphthalene compound involves: bromination of naphthalene dianhydride (NDA) with Br2 and I2 in oleum to obtain inseparable mixture of naphthalene compound of formula (V) (where X is H) and compound (V) (where X is Br), followed by reaction with n-octylamine and HOAc to obtain mixture of naphthalene compound of formula (VI) (where Y1 is H) and compound (VI) (where Y1 is Br) and then reaction with CuCN in dimethylformamide to obtain mixture of mono- and di-imide naphthalene compound of formula (VII) (where Z is H) and (VII) (where Z is CN).X, Y1 and Z=H or Br. Preferred Definitions:    R1 and R2=n-octyl, straight-chain 1-20C fluoroalkyl or 3-10C cycloalkyl;    R3-R6=T1;and    T1=halo, -NO2, -N+(Rb)3, -S(O)2Rb, -S(O)2ORb, -C(O)Rb, -C(O)ORb, -(CH2CH2O)nCH2CH2OH or 1-20C haloalkyl.    At least one of R1 and R2 is straight-chain 1-20C fluoroalkyl or 3-10C cycloalkyl. At least one of R3-R6 is T1.    SPECIFIC COMPOUNDS - N,N'-bis(n-Octyl)-2-cyanonaphthalene-1,4,5,8-bis(dicarboximide), N,N'-bis(n-octyl)-2,6- dicyanonaphthalene-1,4,5,8-bis(dicarboximide), N,N'-bis(n-octyl)-2-bromonaphthalene-1,4,5,8-bis(dicarboximide) and N,N'-bis(n-octyl)-2,6-dibromonaphthalene-1,4,5,8-bis(dicarboximide) are specifically claimed as mono- and di-imide naphthalene compounds.    EXAMPLE - To a flask was added 2,6-dibromonaphthalene-1,4,5,8-tetracarboxylic dianhydride (NDA-Br2) (2.175 g), N-methyl pyrrolidone (100 ml), glacial acetic acid (50 ml) and n-octylamine (8.2 ml). The mixture was stirred at 85 degrees C under N2 for 6 hours. After cooling to room temperature, the mixture was poured into methanol (250 ml) and placed in a -10 degrees C freezer overnight. After worked up, N,N'-bis(n-octyl)-2,6-dibromonaphthalene-1,4,5,8-tetracarboxylic diimide (NDI-8Br2) (1.5084 g, yield 46%) was obtained. To a flask was added CuCN (0.741 g), NDI-8Br2 (0.258 g) and dimethylformamide (50 ml). The mixture was stirred under N2 for 7 hours at 150 degrees C. After the mixture had cooled to room temperature, the solvent was removed. The crude product was continuously extracted with chloroform, filtered, and the filtrate evaporated and dried. After worked up, N,N'-bis(n-octyl)-2,6-dicyanonaphthalene-1,4,5,8-bis(dicarboximide) (97 mg, yield 45%) was obtained.