Non concerted pathways in the generation of dehydroarenes by thermal decomposition of diaryliodonium carboxylates.

Cyclic Hypervalent Iodine Reagents for Atom‐Transfer Reactions: Beyond Trifluoromethylation

“…Arylation reactions with aryl benziodoxolone such as 7 to form C À No rC À Ob onds are well-established, with and without ametal catalyst. [46] They proceed with high selectivity for the transfer of the 2-carboxybenzoic acid group.I n2 013, Zhdankin and co-workers reported that ortho-substituted phenylbenziodoxolone 78 displayed enhanced reactivity,a nd could be easily transformed into 2-hydroxy-or 2-azidobenzoic acids 79 and 80 in high yields (Scheme 16). [11d] Thealkynylation of nitrogen and oxygen nucleophiles has been mostly achieved by using alkynyliodonium salts.…”

Iodonium Salts as Benzyne Precursors

“…For example, the reaction of reagent 45 with tetraphenylcyclopentadienone 59 affords 1,2,3,4‐tetraphenylanthracene 60 in high yield (Scheme ) . This result was superior to the reaction of 2‐naphthyl‐aryliodonium‐3‐carboxylate with 59 under heating conditions …”

“…[30] Phenylbenziodoxole and substituted phenylbenziodoxoles have been employed as the effective aryne sourcesinthe pres-ence of common benzyne trapping compounds such as antracene, 1,3-diphenylisobenzofuran, and tetracyclone compounds. [44,55,57,[61][62][63][64] For example, the reaction of antracene 17 using 5-nitro-2-phenylbenziodoxole 18 as aryne speciesprecursor under reflux conditions gave the corresponding 2-nitrotriptycyne 19 in 43 %y ield, [61] and the reactiono ft etracyclone compounds 20 using phenylbenziodoxole 5 in g-butyrolactone at reflux conditions led to the corresponding tetraphenylnaphthalenecompounds 21 in 56-79% yields (Scheme 7). [55] 1-Phenylbenziodoxole 5 is ap articularly useful reagent for the reactions leading to new carbon-heteroatom bond formation.…”

“…[84] This result was superior to the reaction of 2-naphthyl-aryliodonium-3-carboxylate with 59 under heating conditions. [64] Heteroaromatic analogueso fr eagent 48,p henyl[4-(trimethylsilyl)thien-3-yl]iodonium triflate 46, [85,86] and [1-tert-butoxycarbonyl-4-(trimethylsilyl)-1 H-pyrrole-3-yl]iodonium triflate 47, [87] have been developed. Reagents 46 and 47 can react, for example, with furan in the presence of fluoride source to form the corresponding products of cycloadditioni nl ow to moderate yields.…”

100 Jahre Didehydroaromaten

“…Zwar wurde ein Transient bei m / z =76 mit einer Lebensdauer von 400 μs beobachtet; dieser konnte jedoch aufgrund der Komplexität des Produktspektrums nicht eindeutig 3 zugeordnet werden (Schema ). Daneben gab es aus Abfangexperimenten mehrere indirekte Hinweise auf die Existenz von 3 48–50…”