70445-90-8Relevant academic research and scientific papers
Addition Reactions of Benzothiophen. Part 1. Self-addition and Addition of Simple Aromatic Hydrocarbons
Clark, Peter David,Clarke, Kenneth,Ewing, David F.,Scrowston, Richard M.
, p. 677 - 685 (2007/10/02)
Benzothiophen undergoes facile addition reactions across the 2,3-bond when treated with aluminium chloride in an appropriate solvent at 0 or 20 deg C.In carbon disulphide or dichloromethane, it undergoes self-addition to give two or more of the four possible 2- or 3-(2- or 3-benzothienyl)2,3-dihydrobenzothiophens (3)-(6).In the presence of an aromatic solvent, the dimerization reaction just mentioned predominates at low temperatures (0 deg C or below), or at room temperature if the solvent is benzene, chlorobenzene, t-butylbenzene, isopropylbenzene, or 1,3,5-trimethylbenzene.At room temperature, in toluene, ethylbenzene, and 1,2- or 1,4-dimethylbenzene, solvent addition occurs to give a mixture of the corresponding 2- and 3-aryl-2,3-dihydrobenzenethiophens.At 80 deg C, benzene and toluene give the fully aromatic 2-arylbenzothiophen.The reactions are discussed in terms of an ionic mechanism involving protonation of benzothiophen by moist aluminium chloride and reaction of the resulting electrophile with benzothiophen or with an aromatic substrate.
