Preparation, Characterization, and Reactivity of Aliphatic Amino Iodane(III) Reagents

Abstract

The preparation of a new class of aliphatic amino iodane(III) reagents has been realized with the N-TMSÀ amine and acetoxybenziodazole participated in the formation of NÀ I bond. The amino-containing iodane(III) reagent 2 d was characterized by single-crystal X-ray diffraction, which revealed the expected hypervalent iodane distorted T-shaped geometry. A practical copper-catalyzed, directed electrophilic amination of aryl amines employing amino-iodane(III) as amination agents was disclosed that proceeded smoothly without external additives.

Hypervalent Iodine(III) Reagents with Transferable Primary Amines: Structure and Reactivity on the Electrophilic α-Amination of Stabilized Enolates

“…Single-crystal X-ray analysis revealed a distorted T-shaped geometry similar to that of previously reported N-bound hypervalent iodine reagents. Interestingly, the N–I bond lengths in all 2a – d compounds were found to vary between 2.029(11) and 2.041(5) Å (Table S2 (SI)), and were shorter than those of any of the already reported N-bound cyclic hypervalent iodine reagents. ,− …”

“…In the past decades, hypervalent iodine reagents have showed great promise for oxidative transformations. , Among these, benziodoxolones and benziodoxoles have received particular attention due to their enhanced stability when compared with the acyclic analogues. , Many cyclic hypervalent iodine reagents with transferable nitrogen moieties have been reported, successfully delivering azides ( I ), − amides or sulfonamides ( II ), , sulfoximines ( III ), , imines ( IV ), carbazoles ( V ), and aliphatic cyclic amines ( VI ) (Figure ). However, there are still no unified strategies for oxidative amination using hypervalent iodine reagents.…”

“…The transfer of imine groups, as reported by Minakata using the (diarylmethylene)­amino-containing iodane IV , is an interesting approach, effectively allowing the transfer of imine radicals . Carbazole- and cyclic-amine-bearing iodanes V and VI also allow the transfer of the respective aromatic or aliphatic amines, with the latter representing the first aliphatic amine-bearing hypervalent iodine reagent.…”

Recent Progress in Synthetic Applications of Cyclic Hypervalent Iodine(III) Reagents

“…Alternatively, amino groups can be directly transferred to organic substrates by using the corresponding benziodoxole derivatives as the group transfer reagents. [39][40][41][42][43][44][45][46][47][48][49] Several such reagents can be efficiently prepared by ligand exchange reactions of substituted benziodoxoles with the corresponding nitrogen compounds. Most of these reagents are stable and can be conveniently handled.…”

Reactivity of Hypervalent Iodine(III) Reagents Bearing Transferable N‐Based Groups

“…The synthesis of a new class of aliphatic amino iodane(III) reagents 21 , was reported by Chen and co‐workers [59] . The aliphatic amino iodine(III) reagent 21 a was obtained in 94 % yield by reaction of N ‐TMS‐morpholine 80 a with acetoxybenzio‐doxolone 79 , in the presence of KF as additive (Scheme 27).…”