1370359-47-9

Upstream product

• 1182245-75-5 2,7-bis(butoxycarbonyl)-3,6-dichlorobenzo[1,2-b:6,5-b′]dithiophene 
• 5720-06-9 2-Methoxyphenylboronic acid 
• 16323-43-6 1,4-phenylenediacrylic acid 
• 1365333-82-9 3,6-dichloro-2,7-bis(chlorocarbonyl)benzo[1,2-b:6,5-b′]dithiophene 

Relevant academic research and scientific papers

Cyclization of 1,4-phenylenediacrylic acid with thionyl chloride and subsequent Suzuki-Miyaura reactions revisited. the products are benzo[1,2-b;5,6-b′]dithiophenes and not benzo[1,2-b;4,5-b′] dithiophenes

The reaction of 1,4-phenylenediacrylic acid with thionyl chloride was reinvestigated. In earlier reports [Liebigs Ann. Chem. 1980, 1172; Heterocycles 1995, 41, 2691; Adv. Synth. Catal. 2009, 351, 2683] it was claimed that 3,7-dichlorobenzo[1,2-b;4,5-b′]dithiophenes were formed in these reactions. Herein, we provide unambiguous evidence that the assignment of these structures is wrong and that, in contrast, 3,6-dichlorobenzo[1,2-b;5,6-b′] dithiophenes are formed. As a consequence, the structures of these parent molecules and of numerous aryl-substituted derivatives prepared by Pd-catalyzed cross-coupling reactions have to be revised. As many of these dithiophenes were reported to show interesting optical, thermal and electronic properties, the theoretical explanations for these properties have to be reconsidered in the light of the corrected structures reported herein. Our structural assignments are based on X-ray crystal structure analyses of the parent molecules and on NMR spectroscopic studies of the first unsymmetrical derivatives. Besides, mechanistic investigations based on quantum chemical calculations have been carried out which support the formation of the 3,6-dichlorobenzo[1,2-b;5,6- b′]dithiophene isomers. Copyright

Selective Synthesis, Characterization of Isomerically Pure Arylated Benzo[1,2- b:6,5- b ′]dithiophenes by Regioselective Suzuki-Miyaura Reaction and Evaluation of the Catalytic Properties of Nickel versus Palladium Complexes

Selective synthesis of isomerically pure, angular-shaped benzo[1,2-b:6,5-b′]dithiophenes and various aryl-substituted analogues via the regioselective Suzuki-Miyaura cross-coupling reaction is described. The structural assignments of symmetrical and unsymmetrical derivatives of benzodithiophenes and coumarin-type polyheterocycles are based on X-ray crystallography and spectroscopic studies. A comparative study of nickel versus palladium complexes demonstrated that the nickel complex NiCl2(dppe) is more effective in terms of reactivity and yields than palladium catalysis in the Suzuki-Miyaura cross-coupling of hindered 3,6-dichlorobenzo[1,2-b:6,5-b′]dithiophenes with arylboronic acids.