TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (claimed): Preparing at least one tetracene tetracarboxylic diimide compound of formula I involves causing a halogenocompound of Formula A to react with a first 9-stannafluorene compound of formula B-I and, optionally in addition, with another 9-stannafluorene compound of formula B-II so as to form the at least one compound complying with formula I.X=halogen atom, preferably a bromine atom.Preferred Compound: The halogenocompound is of formula A-II and this one is caused to react with one and only one 9-stannafluorene compound of formula B-I, to form either a mixture of two isomers of formulae IV and V when formula B-I is asymmetrical, or a single compound of formula IV=V when formula B-I is symmetrical (R2=R7, R3=R6, and R4=R5). Some compounds complying with formula I are formed, and at least one of them is separated from the other ones, so as to provide one and only one tetracene tetracarboxylic diimide compound of formula I; or one or more compounds not complying with formula I are formed as by-products, and the at least one compound complying with formula I is separated from the by-products, so as to provide the at least one tetracene tetracarboxylic diimide compound of formula I. Preferred Process: Separation is achieved by distillation or chromatography techniques, such as column chromatography on silica gel. Preferred Device: The electronic device is n-channel field-effect transistor. Preferred Definitions:    R1 and R8= identical to each other, selected from solubilizing groups, and 1-30C alkyls, preferably 4-12C alkyls; and    R2-R7, and R9-R14=H, or at least one of R2-R7, and R9-R14 is an electron-withdrawing group; preferably: (i) R2 and R14 are identical to each other; (ii) R3 and R13 are identical to each other; (iii) R4 and R12 are identical to each other; (iv) R5 and R11 are identical to each other; (v) R6 and R10 are identical to each other; and (vi) R7 and R9 are identical to each other; or (i) R2 and R9 are identical to each other; (ii) R3 and R10 are identical to each other; (iii) R4 and R11 are identical to each other; (iv) R5 and R12 are identical to each other; (v) R6 and R13 are identical to each other; and (vi) R7 and R14 are identical to each other; or (i) R2 and R7 are identical to each other; (ii) R3 and R6 are identical to each other; (iii) R4 and R5 are identical to each other; (iv) R9 and R14 are identical to each other; (v) R10 and R13 are identical to each other; and (vi) R11 and R12 are identical to each other; or (i) R1 and R8 are identical to each other; (ii) R2, R7, R9 and R14 are identical to each other; (iii) R3, R6, R10 and R13 are identical to each other; and (iv) R4, R5, R11 and R12 are identical to each other, the tetracene tetracarboxylic diimide compound being preferably a compound of formula II; tetracene tetracarboxylic diimide compound being more preferably a compound of formula III, the tetracene tetracarboxylic diimide compound being still more preferably the tetracene tetracarboxylic diimide compound of formula III where R1 is 1-30C alkyl and where R3 is H; where the exception of a single compound of formula I where R1 and R8 are n-octyl and where R2-R7, R9-R13 are hydrogen; the 1-30C organic groups are electron-withdrawing groups selected from cyano, 1-30C acyls, halogens, 1-30C perhalogenocarbyls, 1-30C perhalogeno-oxycarbyls, 1-30C partially halogenated hydrocarbyls having a halogen atom over hydrogen atom molar ratio of at least 0.50 and 1-30C partially halogenated oxyhydrocarbyls having a halogen atom over hydrogen atom molar ratio of at least 0.50; and where the 1-30C organic groups are solubilizing groups selected from 1-30C hydrocarbyls, 1-30C oxyhydrocarbyls, 1-30C partially halogenated hydrocarbyls having a halogen atom over hydrogen molar ratio below 0.50 and 1-30C partially halogenated oxyhydrocarbyls having a halogen atom over hydrogen molar ratio below 0.50.    EXAMPLE - No suitable example given.