TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Disclosed): Benzo(b)naphtho(2,1-d)furan derivatives of formulae (II) and (III) are coupling-reacted, to obtain benzo(b)naphtho(2,1-d)furan derivative (I).Y1,Y2=halo, trifluoromethyl sulfonyloxy or group of formula: -B(OX)2 (a);andX=H or alkyl group.(i) When two X are alkyl, two X are coupled to form ring; and (ii) When Y1 or Y2 is group (a), then other is halo. Preferred Composition: The field-effect transistor has a gate electrode (12), a gate insulating film (13), a source electrode (14), a drain electrode (15), and an organic semiconductor layer (16). The organic semiconductor layer contains p-type-semiconductor material and n-type-semiconductor material. The p-type-semiconductor material and/or n-type-semiconductor material contains the benzo(b)naphtho(2,1-d)furan derivative (I). Preferred Process: The organic semiconductor layer is provided, such that the gate electrode is opposed through the gate insulating film. The source electrode and drain electrode are connected with organic semiconductor layer. The organic semiconductor layer optionally covers top of drain electrode and source electrode. The organic semiconductor layer is formed by coating composition containing the benzo(b)naphtho(2,1-d)furan derivative (I), and vapor-depositing benzo(b)naphtho(2,1-d)furan derivative (I). Preferred Definitions:    R1-R4=H.    SPECIFIC COMPOUNDS - 68 Benzo(b)naphtho(2,1-d)furan derivatives are disclosed e.g. (9,9')bi(benzo(b)naphtho(2,1-d)furan) of formula (Ia), 3,3'-diphenyl-(9,9')bi(benzo(b)naphtho(2,1-d)furan), 3,3'-di-naphthalen-2-yl-(9,9')bi(benzo(b)naphtho(2,1-d)furan), 5,5'-di-naphthalen-2-yl-(9,9')bi(benzo(b)naphtho(2,1-d)furan) and 3,3'-Di-thiophen-2-yl-(9,9')bi(benzo(b)naphtho(2,1-d)furan).    EXAMPLE - Mixture of 9-chloro-benzo(b)naphtho(2,1-d)furan (610 mg), bis(triphenylphosphine)nickel(II) chloride (13 mg), triphenylphosphine (66 mg), 2,2'-bipyridine (3.2 mg), zinc powder (68 mg) and anhydrous N,N-dimethylacetamide (4 mL) were stirred at 80 degrees C for 12 hours, obtained product was added to water, dichloromethane-extracted, and solvent distillation was performed, to obtain colorless solid (420 mg) of (9,9')bi(benzo(b)naphtho(2,1-d)furanyl), with yield of 80%.