Preparation and X-ray Structural Study of 1-Arylbenziodoxolones

Abstract

Various 1-arylbenziodoxolones can be conveniently prepared from 2-iodobenzoic acid and arenes by a one-pot procedure using Oxone (2KHSO5·KHSO4·K2SO4) as an inexpensive and environmentally safe oxidant. This procedure is also applicable for the synthesis of the 7-methylbenziodoxolone ring system using 2-iodo-3-methylbenzoic acid as starting compound. Structures of four 1-arylbenziodoxolone derivatives were established by single-crystal X-ray diffraction analysis. An enhanced reactivity of 1-aryl-7-methylbenziodoxolones toward nucleophiles compared to unsubstituted 1-arylbenziodoxolones has been found.

Synthesis, Characterization and Unusual Reactivity of Vinylbenziodoxolones—Novel Hypervalent Iodine Reagents

“…The crystals were prepared by layering a solution of 6 a in DMSO with diethyl ether and submitted to single crystal X‐ray analysis (Figure ). The molecular conformation has a distorted T‐shape with an O9‐I1‐C10 angle of 165.8°, which is similar to the reported arylbenziodoxolones and alkynylbenziodoxolones . The bond angle O9‐I1‐C6 is 72.9° and the C6‐I1‐C10 angle of 93.7° are also similar to previous reports, as are the bond lengths I1−C6 of 2.121 (Å) and I1−C10 of 2.100 (Å).…”

“…The bond angle O9‐I1‐C6 is 72.9° and the C6‐I1‐C10 angle of 93.7° are also similar to previous reports, as are the bond lengths I1−C6 of 2.121 (Å) and I1−C10 of 2.100 (Å). The I1−O9 bond length of 2.51 Å is significantly larger than in alkynylbenziodoxolones, but in similar length as arylbenziodoxolones . This bond length trend is in agreement with the larger trans influence exerted by vinyl and aryl groups compared to alkynyl and trifluoromethyl groups …”

Bench‐Stable Electrophilic Indole and Pyrrole Reagents: Serendipitous Discovery and Use in C–H Functionalization

“…The developed protocol based on the catalytic use of a relatively mild Lewis acid is noteworthy, as most syntheses of alkynyl, vinyl or aryl benziodoxolone reagents usually require a stoichiometric amount of strong Lewis or Brønsted acid. [ ][ ][ ] In fact, these reported procedures were not successful for the synthesis of IndoleBX 21 , as they led to complete decomposition of indole 14 . Furthermore, IndoleBX 21 displayed excellent thermal stability properties when compared to indole iodonium salts.…”

“…This is noteworthy, as controlling the selectivity of aryl transfer from iodonium salts is generally challenging . Furthermore, transfer of the benzoic acid is usually observed in the reaction of aryl benziodoxolones with nucleophiles . Under these conditions, no product was obtained with either iodo‐ or bromo‐indoles 50 and 51 .…”

Alternative Strategien mit Iod: schneller Zugang zu bisher unzugänglichen Iod(III)‐Verbindungen

“…Ihre Syntheseanwendungen umfassen Oxidation, [2] Halogenierung, [3] Kohlenstoff-Kohlenstoff-Bindungsbildung, [4] Aminierung [5] und Oxygenierung. Ihre Synthese erfolgt normalerweise durch die Reaktion von Iodarenen mit Oxidationsmitteln wie Oxone, [7] meta-Chlorperbenzoesäure, [8] Peressigsäure, [9] Natriumperborat [10] oder Selectfluor [11] in Gegenwart von Carbonsäuren. Ihre Synthese erfolgt normalerweise durch die Reaktion von Iodarenen mit Oxidationsmitteln wie Oxone, [7] meta-Chlorperbenzoesäure, [8] Peressigsäure, [9] Natriumperborat [10] oder Selectfluor [11] in Gegenwart von Carbonsäuren.…”