2-Iodoxybenzoic acid ditriflate: the most powerful hypervalent iodine(v) oxidant

Abstract

A new powerful hypervalent iodine(v) oxidant, a ditriflate derivative of 2-iodoxybenzoic acid (IBX), was prepared by the reaction of IBX with trifluoromethanesulfonic acid and characterized by single crystal X-ray crystallography.

Recent discoveries on the structure of iodine(iii) reagents and their use in cross-nucleophile coupling

“…This is also showcased by the ongoing interest in the development of new iodine(III) and iodine(V) compounds. 119,[158][159][160][161] The use of ketones and their derivatives is particularly interesting, because the 2e À oxidation gives rise to an a-carbocationic ketone synthon, which prone to undergo carbocationic rearrangements. This will continue to inspire chemists to design new sequences and serve as an engine for serendipitous discovery.…”

Benziodoxole-Derived Organosulfonates: The Strongest Hypervalent Iodine Electrophiles and Oxidants

“…Very recently, we reported the preparation and reactivity of the strongest iodine(V) oxidant, 2-iodoxybenzoic acid ditriflate (9). 39 IBX-ditriflate (9) was prepared by treatment of 2-iodoxybenzoic acid (55) with a slight excess of trifluoromethanesulfonic acid in CH 2 Cl 2 /CF 3 CO 2 H solution (Scheme 11). Product 9 precipitated from the solution as a sensitive to moisture, crystalline solid that could be isolated from the reaction mixture by filtration.…”

“…Finally, we were able to obtain X-ray crystallographic data for 9 demonstrating a very complex solid-state assembly formed by primary bonds and various intermolecular secondary interactions. 39 Structural formula 9 shown in Scheme 11 gives the best description of a simplified molecular structure of this compound. The hypervalent iodine atom in molecule 9 has short primary bonds to carbon and three oxygen atoms and secondary contacts to the oxygen atoms of two triflates (2.985 Å and 2.820 Å), which have a significant ionic character.…”

Reactions promoted by hypervalent iodine reagents and boron Lewis acids

“…Hypervalent iodine compounds are valuable reagents, having broad applicability in organic synthesis, 6 and present themselves as non-toxic and environmentally benign alternatives to heavy metals. 7 Moreover, hypervalent iodine compounds are commonly used in oxidation reactions, [8][9][10] they have also found widespread utilisation in functionalisations, and are ideally suited for applications in total synthesis as well as the pharmaceutical industry. 11,12 When combined with boranes, typically Lewis acid, activation of the hypervalent iodine compound occurs as shown in Scheme 1.…”