Formation of benzo[c]thiophen-1-aminium iodide by the reaction of o-alkynylbenzothioamide with iodine

Generation of Aryl Radicals from Aryl Halides: Rongalite-Promoted Transition-Metal-Free Arylation

A new and practical method for the generation of aryl radicals from aryl halides is reported. Rongalite as a novel precursor of super electron donors was used to initiate a series of electron-catalyzed reactions under mild conditions. These transition-metal-free radical chain reactions enable the efficient formation of C-C, C-S, and C-P bonds through homolytic aromatic substitution or S_RN1 reactions. Moreover, the synthesis of antipsychotic drug Quetiapine was performed on gram scale through the described method. This protocol demonstrated its potential as a promising arylation method in organic synthesis.

Formation of Benzimidazoisoquinolinium and Benzimidazoisoindolinum Cyclic Systems by the Reaction of 2-(2-Alkynylphenyl)benzimidazoles with Iodine and Iodine-Iodine Interaction Including Halogen Bonding in Their Crystal Structures

The reaction of 2-(2-alkynylphenyl)benz[d]imidazoles with molecular iodine constructed 5- and 6-membered rings as novel organic salts in high yield. The constituted number of ring systems was influenced by the substituent at the triple bond: 6-membered rings were formed from compounds bearing aryl substituents, whereas 5-membered ones were obtained from compounds with hydrogen or alkyl substituents. The products were obtained with triiodide as a counteranion; however, compounds with iodide were also obtainable under certain conditions. We also revealed that they had an iodine-iodine interaction included in halogen bonding between an iodo moiety of the cation and a triiodide or iodide of the counteranion. The iodine-iodine interaction was formed with greater preference than the electrostatic interaction between the cationic atom and triiodide or iodide.