2,2':5',2''-Terthiophene → (2,2':5',2''-Terthiophenyl)-5-carbonitrile

Participants

Reaction Steps

To a solution of α-terthienyl (2.46 g, 0.010 m) in methylene chloride (20 ml), was added chlorosulfonyl isocyanate (1.75 ml) in methylene chloride (15 ml). A yellow solid separated almost at once. The reaction mixture was stirred for 2 h and left overnight. Dimethyl formamide (5.0 ml) was added to the ice-cold reaction mixture dropwise. Addition of water (40 ml) precipitated a yellow solid insoluble in methylene chloride. The latter was removed in vacuo and the yellowish green solid was collected in a Buchner funnel and washed with water. Yield: 2 g; m.p. 122°-125° C. Recrystallization from the minimum amount of boiling ethanol-benzene(1:1) afforded 1.6 g of product(58.6% crude yield).

Provenance & Evidence