Oxidative Rearrangements with Hypervalent Iodine Reagents

Abstract

Hypervalent iodine chemistry is used as an important tool in synthetic and natural product chemistry. A number of hypervalent iodine reagents can be used to generate the functionalizations on various scaffolds by several chemical approaches including oxidation reactions, oxidative cyclization reactions, and rearrangements. Recently, these reagents have been employed to develop a variety of oxidative rearrangements. In this review article, various aspects of recently developed oxidative rearrangements using iodine(III) and iodine(V) reagents are described. 1 Introduction 2 Oxidative Rearrangements 2.1 1,2-Aryl Group Migrations 2.2 Hofmann Rearrangements 2.2.1 Hofmann Rearrangements without Cyclizations 2.2.2 Hofmann Rearrangements with Cyclizations 2.3 Ring Contractions 2.4 Ring Expansions

The mechanochemical synthesis of quinazolin-4(3H)-ones by controlling the reactivity of IBX

“…Their easy availability, high stability, controlled oxidizing ability, and environmentally benign nature make them highly suitable for the development of new synthetic transformations [13–17]. The chemistry of iodine(V) reagents has been well documented in a number of reviews [18–20]. In continuation of our research focus on the development of synthetic methods using iodine-based reagents [21–26], we here report a method for the synthesis of quinazolin-4(3 H )-ones [27–28] (Fig.…”

A Unified Approach to Mono- and 2,3-Disubstituted N–H Indoles

“…Amides or carbamates would likely favor preferential activation of the 2-alkenyl moiety by hypervalent iodine reagents such as PIFA or PhIO, opening up the possibility of a formal switch of the R 2 and R 3 substituents via a cyclopropyl phenonium ion intermediate. 3c 4a f 1,2-Aryl migration was first reported in PIFA oxidation of α-substituted styrenes to the corresponding ketones. 3c Partial migration (deuterium scrambling) was also observed for oxidation of 2-alkenyl aniline N -tosylates and carbamates with different hypervalent iodines.…”

“…3c 4a f 1,2-Aryl migration was first reported in PIFA oxidation of α-substituted styrenes to the corresponding ketones. 3c Partial migration (deuterium scrambling) was also observed for oxidation of 2-alkenyl aniline N -tosylates and carbamates with different hypervalent iodines. 4a 4f In contrast, PIFA oxidation of 2-aryl aniline derivatives likely proceeds with N -oxidation, since oxidation of the 2-aryl group seems improbable.…”

Hypervalent iodine chemistry and light: photochemical reactions involving hypervalent iodine chemistry

“…[18][19][20][21][22][23] Additionally, these reagents have been successfully applied to obtain several synthetic transformations including cyclizations, [24][25][26][27][28][29][30] aminations, [31][32][33][34] functionalizations of carbonyl compounds, [35][36][37][38] arylations, [39][40][41] atom-transfer reactions, 42 cycloaddition reactions, [43][44][45] and oxidative rearrangements. [46][47][48][49] Moreover, these reagents have been used as catalyst to develop number of organic transformations. [50][51][52][53][54] In recent years, hypervalent iodine reagents received a particular attention in visible-light photoredox catalysis.…”