33775-94-9Relevant articles and documents
Synthesis of [1]Benzothieno[3,2- b][1]benzothiophene Derivatives via Successive Iodocyclization/Photocyclization of Alkynes
Kitamura, Tsugio,Morita, Kazuhiro,Nakamori, Haruka,Oyamada, Juzo
, p. 4191 - 4199 (2019)
A new synthetic method for [1]benzothieno[3,2-b][1]benzothiophene derivatives (BTBTs) was developed. The present method consists of iodocyclization of 1,2-bis(2-methylthiophenyl)ethynes and photolysis of 3-iodo-(2-methylthiophenyl)benzo[b]thiophenes. With 1,2-bis(2-methylthiophenyl)ethynes treated with I2/PhI(OAc)2 in CH2Cl2 at room temperature, selective cyclization at sulfur took place to give 3-iodo-(2-methylthiophenyl)benzo[b]thiophenes in good yields. Irradiation of the iodinated benzo[b]thiophenes with a high-pressure Hg lamp (>290 nm) provided BTBTs in good yields. Furthermore, the present method was applied to the synthesis of bis[1]benzothieno[2,3-d;2′,3′-d′]benzo[1,2-b;4,5-b′]dithiophene (BBTBDT).
Facile syntheses of 3-trifluoromethylthio substituted thioflavones and benzothiophenes via the radical cyclization
Wang, Lu,Wang, Huaiyu,Meng, Weidong,Xu, Xiu-Hua,Huang, Yangen
, p. 389 - 392 (2020/03/04)
3-CF3S substituted thioflavones and benzothiophenes were achieved via the reactions of AgSCF3 with methylthiolated alkynones and alkynylthioanisoles, respectively, promoted by persulfate. This protocol possesses good functional group tolerance and high yields. Mechanistic studies suggested that a classic two-step radical process was involved, which includes addition of CF3S radical to triple bond and cyclization with SMe moiety.
Copper-catalysed aromatic-Finkelstein reactions with amine-based ligand systems
Jin, Xiaodong,Davies, Robert P.
, p. 2110 - 2117 (2017/07/22)
A new efficient and low-cost ligand, diethylenetriamine, has been utilised to promote the iodination of 16 different bromo-substrates via the copper catalysed Finkelstein halogen exchange reaction under mild conditions. In contrast to earlier methods, the use of inert atmosphere conditions was not required to obtain high yields and purity. Studies on the speciation of the catalyst in solution indicate rapid disproportionation of copper(i) in the presence of diethylenetriamine to give copper(0) and a bis-ligated copper(ii) complex which is characterised by X-ray diffraction. This copper(ii) complex was also shown to be catalytically active in the halogen exchange reaction. In contrast, no significant disproportionation was observed using dimethylethylenediamine as the ligand, and the solid-state structures of a copper(i) dimeric complex and a 2D polymeric network of copper(i) iodide tetramers are reported. The catalytic activity of diethylenetriamine and dimethylethylenediamine with both copper(i) and copper(ii) salts are compared, and possible mechanistic implications discussed.