Cyclic Haloiodanes: Syntheses, Applications and Fundamental Studies

Abstract

Hypervalent iodine reagents are powerful tools in contemporary organic synthesis. They have found numerous applications in modern oxidative transformations. The unique reactivity of hypervalent iodine allows access to unconventional electrophilic synthons. For example, electrophilic halogenation chemistry has been greatly expanded by the study of various haloiodanes. Cyclic λ3‐haloiodanes are versatile reagents which can promote reactions such as halogenations, halocyclizations and oxidations. Their peculiar reactivity sets them apart from traditional sources of electrophilic halogens. Furthermore, they offer a broad range of reactivities which have been exploited in more diversified transformations. This review summarizes the different syntheses and derivatives of these cyclic haloiodanes, their applications and mechanistic insights as well as the relevant computational, structural and kinetic studies.

Updates on hypervalent-iodine reagents: metal-free functionalisation of alkenes, alkynes and heterocycles

“…2). 15,40 Among them, functionalised benziodoxol(on)e derivatives are one of the significant classes of HVI reagents due to their wide use in diverse functional group transformations (alkynyl, -F, -CF 3 , -N 3 , -OAc, etc.). The chemoselective introduction of the fluoro group in complex molecules, such as peptides and proteins allows the use of 19 F NMR for the determination of the protein structure and dynamics and monitoring the progress of a reaction.…”

“…[27][28][29][30][31][32][33][34][35][36][37] The chemistry of specific classes of HVI compounds has been summarised from time to time in various specialised reviews and accounts. [38][39][40][41][42][43][44][45] Thus, the present article will not be inclusive but will emphasise only the key aspects and most relevant components for this review. This article aims to give a brief synopsis of the HVI chemistry, focusing mainly on the metalfree syntheses that have taken place in the past couple of years.…”

Synthesis and Evaluation of Fluorous-Tagged and Polystyrene-Supported Precursors for Fluoro-benziodoxole

“…Paper / PSP / Special Topic 5) 6315( 15) 8284( 6) 1006( 3) 189( 4) F( 6) 8074(10) 8164( 8) 1798( 6) 242( 5) F (7) 3521( 16) 9676( 14) 1327(8) 321(9) F( 8) 4613( 19) 9565( 6) 2325( 4) 244( 5) F( 9) 5134( 17) 11772( 7) 1628( 5) 244( 5) F( 10) 8050( 30) 10740( 15) 1903( 6) 356(10) F (11) 6027( 16) 10815( 8) 458( 3) 206(4) F( 12) 8883( 11) 10238( 6) 824( 4) 198(4) F( 13) 6086( 14) 13174( 7) 453( 5) 206( 4) F( 14) 8620(20) 12930(10) 1117( 4) 271( 6) F (15) 8718( 14) 12148(8) -393(4) 183(3) F (16) 11163 (15) 12062( 12) 247( 6) 257( 6) F (17) 9464( 18 This article is protected by copyright. All rights reserved.…”

“…11 Hypervalent iodine (HVI) compounds are multifunctional reagents that serve as transition-metal surrogates in numerous processes, 12 and Synthesis Paper / PSP / Special Topic Template for SYNTHESIS Thieme fluoro-benziodoxole 1 has attracted significant attention due to its ability to promote similar pseudo-electrophilic fluorinations under relatively mild conditions. 13,14 It has been prepared via oxidative fluorination of iodoalcohol 2 using either Selectfluor 15 or AgF2, 16 though it is more commonly made via anionic fluoride exchange from ligands such as chloride (3, 94% yield), hydroxide (4, 94% yield), trifluoroacetate (5, 63%) and tosylate (6, 46%). 13b, 13c Recently, researchers have also succeeded in translating its established reactivity to radiofluorination.…”

Convenient Synthesis of Benziodazolone: New Reagents for Direct Esterification of Alcohols and Amidation of Amines

“…Iodine(III)-containing heterocycles represent one of the most important classes of hypervalent iodine reagents [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ]. Among them, the five-membered iodine-oxygen heterocycles, which are known by the general name of benziodoxolones, have found wide application in organic synthesis [ 9 , 10 , 11 , 12 , 13 , 14 ].…”