Synthesis of Aryl Iodides from Arylhydrazines and Iodine

Abstract

A metal- and base-free method is developed for the synthesis of aryl iodides from arylhydrazine hydrochlorides and iodine. A wide variety of aryl iodides can be conveniently synthesized by an equimolar reaction of arylhydrazine hydrochlorides and I 2 in dimethyl sulfoxide at 60 °C for 6 h. In the iodination step, arylhydrazines are oxidized by iodine to form arenediazonium salts, which undergo single-electron transfer from iodide anion to give aryl and iodine radicals; subsequent combination of them affords the corresponding aryl iodides.

Reaction of arylhydrazines with diaryl ditellurides in the air: Insight into bimolecular homolytic substitution on tellurium via Aryl–Te bond cleavage

“…One is a photoinduced decomposition of triarylbismuthines and the other is an air‐induced decomposition of arylhydrazines . In the latter method, arylhydrazine hydrochlorides can be employed as an aryl radical source, and by using this method, we successfully developed the arylation of aminoheterocycles and aromatic diamines, the synthesis of unsymmetrical diaryl sulfides and selenides, and the aryl iodide synthesis by the trapping of aryl radicals with I 2 . On the basis of these studies, we have investigated the reaction of arylhydrazine hydrochlorides with diaryl ditellurides to synthesize symmetrical and unsymmetrical diaryl tellurides.…”

Transition-Metal-Free Synthesis of Unsymmetrical Diaryl Tellurides via SH2 Reaction of Aryl Radicals on Tellurium

“…We recently developed a series of carbon–heteroatom bond formation methods, as shown in Scheme 1 . Aryl radicals generated in air by the oxidation of arylhydrazine hydrochlorides or photoirradiation of triarylbismuthines were successfully trapped with I 2 or BBr 3 in dimethyl sulfoxide (DMSO) to give the corresponding aryl halides with high yields ( Scheme 1 a,b) [ 5 , 6 ]. This system was also applicable for the formation of unsymmetrical sulfides and selenides by trapping aryl radicals with (R–X) 2 (X = S, Se) ( Scheme 1 c) [ 7 , 8 , 9 , 10 ].…”

Generation of Aryl Radicals from Aryl Hydrazines via Catalytic Iodine in Air: Arylation of Substituted 1,4-Naphthoquinones

“…Iodine and organic iodides have evolved as efficient and robust reagents or catalysts for the synthesis of organic compounds. 11,12 benign, robust, and inexpensive provides an enormous scope for these reactions in industry if properly harnessed. 14 As a sustainable and viable contribution toward the generation of aryl radicals, we began to think about harnessing molecular iodine as an appropriate catalyst.…”

“…Iodine and organic iodides have evolved as efficient and robust reagents or catalysts for the synthesis of organic compounds. , One of the most remarkable developments in this field is the invention of the catalytic activity of molecular iodine in the formation of diverse C–C, C–O, and C–N bonds. − Interestingly, iodine- and transition-metal-catalyzed reactions are similar and the fact that iodine is environmentally benign, robust, and inexpensive provides an enormous scope for these reactions in industry if properly harnessed …”