Defined Hypervalent Iodine(III) Reagents Incorporating Transferable Nitrogen Groups: Nucleophilic Amination through Electrophilic Activation

Substitution Effects of Hypervalent Iodine(III) Reagents in the Diamination of Styrene

“…Finally, saturation of the coordination sphere of iodine by introduction of an additional NTs 2 moiety generates the bisimido species 4a. 4,6,7 Successful applications of these aminating reagents involve allylic, 8,9 acetylenic, 10 and aromatic 11,12 amination events and the diamination of alkenes. 13 The overall series culminated in an enantioselective diamination of styrenes, 14 which is of unsurpassed efficiency in the field.…”

“…Based on the observations from Scheme 2 and Figure 1, we now propose that the decisive step in the diamination of alkenes with bistosylimide as nitrogen source consists of a dissociative pre-equilibrium ( Figure 2). Previously, this dissociation context had been investigated experimentally for the neutral species 4a, 4 and had been identified by theory as the energetically most demanding step of the diamination reactions of styrene with related bismesylimide. 17 The data presented here imply that the enhanced acceleration with 4d is based on an electronic donor stabilization of the involved cationic intermediate 4+.…”

Iodobenzene Dicarboxylates as Transferrable Oxygen Sources: Synthesis of α-Oxygenated Ketones from Terminal Aryl Alkynes

“…In the control experiments, we found that external HOAc (Table 1, Entry 8) had almost no effect on the reaction yield. On the basis of the results described above, and along with the previous work by Muñiz, [11,14] Hou, [12] and Ochiai, [20] a plausible mechanism for the conversion of alkynes into α-oxygenated ketones is proposed and depicted in Scheme 4. Reaction of the alkyne with PhI(OCOR) 2 2 O, the iodonium ylide III is formed, and further electrophilic addition of (RCO) 2 O to III gives intermediate IV.…”

“…The experimental results demonstrate that PhI(OCOR) 2 itself may serve as a transferrable oxygen source as well as an electrophile and excellent leaving group. [14] Scheme 1 Synthesis of α-oxygenated ketones from terminal aryl alkynes.…”

Iodine(III)‐Mediated para‐Selective Direct Imidation of Anilides

“…[11] In the context of CÀNb ond formation,M uÇiz andc o-workers have reported as ingle example of para-imidationo fabenzylanilide substrate with non-commercially available PhI(NTs) 2 . [12] Furthermore, Zhang and co-workers disclosed ar are example of a para-selective imidation reaction, where 2-alkoxyanilide derivatives were coupled with N-fluorobenzenesulfonimide (NFSI) in the presence of ap alladium catalyst. [13] Herein we report our findings on the oxidative direct imidation of anilides,e xhibiting exclusive regioselectivity for the para position (Scheme 1c).…”