Reactivity of hypervalent iodine(III) reagents bearing a benzylamine with sulfenate salts

• Beatriz Dedeiras,
• Catarina S. Caldeira,
• José C. Cunha,
• Clara S. B. Gomes and
• M. Manuel B. Marques

Beilstein J. Org. Chem. 2024, 20, 3281–3289, doi:10.3762/bjoc.20.272

• . A plausible mechanism is proposed, suggesting a possible radical pathway. Keywords: electrophilic amination; hypervalent iodine reagents; sulfinamide; sulfonamide; Introduction Iodine(III) compounds, known as λ3-iodanes, have been extensively applied in organic synthesis. Although initially used

• distorted T-shaped geometry, consistent with previously reported N–bound hypervalent iodine reagents. Additionally, the N–I bond distance is 2.0454(5) Å, which aligns with our previously reported values [4]. The two aromatic rings are nearly coplanar, exhibiting a dihedral angle of 0.7(3)°. All other bond

• Beatriz Dedeiras Catarina S. Caldeira Jose C. Cunha Clara S. B. Gomes M. Manuel B. Marques LAQV-REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, NOVA FCT , 2829-516 Caparica, Portugal 10.3762/bjoc.20.272 Abstract The reactivity of our recently disclosed hypervalent iodine

Direct trifluoroethylation of carbonyl sulfoxonium ylides using hypervalent iodine compounds

• Radell Echemendía,
• Carlee A. Montgomery,
• Fabio Cuzzucoli,
• Antonio C. B. Burtoloso and
• Graham K. Murphy

Beilstein J. Org. Chem. 2024, 20, 3182–3190, doi:10.3762/bjoc.20.263

• ylides can be derivatized using hypervalent iodine reagents, and our continued efforts towards this will be reported in due course. Experimental Representative procedure for 2,2,2-trifluoroethylation of sulfoxonium ylides An oven dried 5 mL microwave flask containing a magnetic stirrer was charged with

Structure and thermal stability of phosphorus-iodonium ylids

• Andrew Greener,
• Stephen P. Argent,
• Coby J. Clarke and
• Miriam L. O’Duill

Beilstein J. Org. Chem. 2024, 20, 2931–2939, doi:10.3762/bjoc.20.245

• enable access to chemical motifs that are difficult to synthesise using traditional approaches. However, gaps remain in the functionality they can transfer. Specifically, unstabilised alkyl groups are still underrepresented. For the development of new hypervalent iodine reagents to bridge this gap, it is

Recent advances in transition-metal-free arylation reactions involving hypervalent iodine salts

• Ritu Mamgain,
• Kokila Sakthivel and
• Fateh V. Singh

Beilstein J. Org. Chem. 2024, 20, 2891–2920, doi:10.3762/bjoc.20.243

• of the SO2CF3 leaving group from the intermediate. For the late-stage substitution of coumarins, Han and colleagues developed a method, using hypervalent iodine reagents. At 50 °C in the presence of a base, coumarin-based aryliodonium salts are produced. These salts undergo an intramolecular aryl

Hypervalent iodine-mediated cyclization of bishomoallylamides to prolinols

• Smaher E. Butt,
• Konrad Kepski,
• Jean-Marc Sotiropoulos and
• Wesley J. Moran

Beilstein J. Org. Chem. 2024, 20, 2455–2460, doi:10.3762/bjoc.20.209

• enantioselective conjugate addition to α,β-unsaturated pyroglutamic acid derivatives followed by deoxygenation [10], and the enantioselective organocatalytic reaction between 2-acylaminomalonates and α,β-unsaturated aldehydes [11][12]. The development of new synthetic methods using hypervalent iodine reagents has

Hydrogen-bond activation enables aziridination of unactivated olefins with simple iminoiodinanes

• Phong Thai,
• Lauv Patel,
• Diyasha Manna and
• David C. Powers

Beilstein J. Org. Chem. 2024, 20, 2305–2312, doi:10.3762/bjoc.20.197

• Phong Thai Lauv Patel Diyasha Manna David C. Powers Department of Chemistry, Texas A&M University, College Station TX, 77843, USA 10.3762/bjoc.20.197 Abstract Iminoiodinanes comprise a class of hypervalent iodine reagents that is often encountered in nitrogen-group transfer (NGT) catalysis. In

• the potential for chemical non-innocence of fluorinated alcohol solvents in NGT catalysis. Keywords: aziridination; electrochemistry; H-bond activation; hypervalent iodine; nitrene transfer; Introduction Hypervalent iodine reagents find widespread application in selective oxidation chemistry due to

• ]. Iminoiodinanes (ArI=NR) are a subclass of hypervalent iodine reagents that function as nitrene equivalents in synthesis [5][6]. The direct reaction of iminoiodinanes with olefins, which could be envisioned to give rise to aziridines directly, is typically not observed and thus families of transition metal

Solvent-dependent chemoselective synthesis of different isoquinolinones mediated by the hypervalent iodine(III) reagent PISA

• Ze-Nan Hu,
• Yan-Hui Wang,
• Jia-Bing Wu,
• Ze Chen,
• Dou Hong and
• Chi Zhang

Beilstein J. Org. Chem. 2024, 20, 1914–1921, doi:10.3762/bjoc.20.167

• –intramolecular cyclization cascade with excellent chemoselectivity in aqueous CH3CN [25]. Herein, as part of our continuing studies of heterocyclic scaffold synthesis mediated by hypervalent iodine reagents, we present the solvent-dependent chemoselective synthesis of a series of isoquinolinones mediated by PISA

Synthesis of polycyclic aromatic quinones by continuous flow electrochemical oxidation: anodic methoxylation of polycyclic aromatic phenols (PAPs)

• Hiwot M. Tiruye,
• Solon Economopoulos and
• Kåre B. Jørgensen

Beilstein J. Org. Chem. 2024, 20, 1746–1757, doi:10.3762/bjoc.20.153

• radical (potassium nitrosodisulfonate) [13] or catalytic systems like methyltrioxorhenium(VII) (MeReO3) [14] and 2-iodobenzenesulfonic acids (IBS)/Oxone® [15] led to either p-quinones or o-quinones, depending on the substituents in the para-position to the hydroxy group. Recently, hypervalent iodine

• reagents have been explored for the oxidation of polycyclic aromatic phenols (PAPs). Oxidation of 1-naphthol derivatives by bis(trifluoroacetoxy)iodobenzene (BTI) furnished p-naphthoquinones [16]. Other PAPs follow the same pattern forming p-quinones or o-quinones when the para-position is structurally

Divergent role of PIDA and PIFA in the AlX₃ (X = Cl, Br) halogenation of 2-naphthol: a mechanistic study

• Kevin A. Juárez-Ornelas,
• Manuel Solís-Hernández,
• Pedro Navarro-Santos,
• J. Oscar C. Jiménez-Halla and
• César R. Solorio-Alvarado

Beilstein J. Org. Chem. 2024, 20, 1580–1589, doi:10.3762/bjoc.20.141

• different hypervalent iodine reagents for this reaction. To find the correlations between experiments and theoretical calculations, chlorination and bromination of 2-naphthol using PIFA/AlCl3 and PIDA/AlBr3 were carried out. Consequently, we found an excellent correlation between the yield and the energy

Predicting bond dissociation energies of cyclic hypervalent halogen reagents using DFT calculations and graph attention network model

• Yingbo Shao,
• Zhiyuan Ren,
• Zhihui Han,
• Li Chen,
• Yao Li and
• Xiao-Song Xue

Beilstein J. Org. Chem. 2024, 20, 1444–1452, doi:10.3762/bjoc.20.127

• ; machine learning; Introduction Hypervalent iodine reagents are increasingly gaining attention in the fields of organic synthesis and catalysis due to their environmental benefits, accessibility, and cost-efficiency [1][2][3][4][5][6][7][8][9][10][11]. Over the last three decades, a series of cyclic

Oxidative hydrolysis of aliphatic bromoalkenes: scope study and reactivity insights

• Amol P. Jadhav and
• Claude Y. Legault

Beilstein J. Org. Chem. 2024, 20, 1286–1291, doi:10.3762/bjoc.20.111

• metals, inspired by Nature's metalloproteins. However, using toxic and expensive metals is not always practical, making alternative oxidative methodologies more appealing. Enter hypervalent iodine reagents – a leading metal-free choice for oxidation reactions. These robust and low-toxicity reagents have

• -bromoketone derivatives. While we could not further minimize the formation of Ritter-type side products (≈4:1 ratio of α-bromoketone vs Ritter-type side products), noticing these side products from common phenyl tosyloxy iodonium intermediate suggest that hypervalent iodine reagents could be utilized in the

SOMOphilic alkyne vs radical-polar crossover approaches: The full story of the azido-alkynylation of alkenes

• Julien Borrel and
• Jerome Waser

Beilstein J. Org. Chem. 2024, 20, 701–713, doi:10.3762/bjoc.20.64

• , entry 10). The addition of DABCO [18] or TBAI [50], two additives known to activate azidobenziodoxolone (ABX), afforded complex mixtures with no trace of 4a (Table 1, entry 11). Acids or fluorinated alcohols were tested to activate the different hypervalent iodine reagents. While AcOH, TFA and TFE had

• iodine reagents [15][16]. Azidobenziodoxolone, also known as Zhdankin reagent, has often been used under thermal or photochemical conditions to generate the desired azide radical in a controlled fashion. However, recent safety issues arising from the shock and impact sensitivity of the compound led to

• , greatly increasing the molecular complexity of the starting substrate. Using radical chemistry would lead to a regioselective addition of azide radicals to the alkene, forming selectively the most stabilized C-centered radical. A prominent method for the generation of azide radicals relies on hypervalent

Copper-catalyzed N-arylation of amines with aryliodonium ylides in water

• Kasturi U. Nabar,
• Bhalchandra M. Bhanage and
• Sudam G. Dawande

Beilstein J. Org. Chem. 2023, 19, 1008–1014, doi:10.3762/bjoc.19.76

• tuning of the ligand and base combinations [18][19]. Thereafter, copper-catalyzed C–N bond-formation reactions have experienced unprecedented development due to mild reaction conditions and the low cost of copper salts [20][21][22]. On the other hand, hypervalent iodine reagents serve as versatile tools

• in oxidation, C–C, C–X bond formation, rearrangements, and halogenation reactions [23][24][25]. Due to the nontoxic nature, easier preparation, and handling of the hypervalent iodine reagents, many researchers are attracted to unravel the chemistry and reactivity of these reagents. Amongst different

• types of hypervalent iodine reagents, diaryliodonium salts are commonly used reagents for the N-arylation of nitrogen-containing compounds, particularly for N-arylation of amines under catalyst-free conditions either in the presence of additives or at higher temperatures [26][27][28][29][30][31][32

Two-step continuous-flow synthesis of 6-membered cyclic iodonium salts via anodic oxidation

• Julian Spils,
• Thomas Wirth and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2023, 19, 27–32, doi:10.3762/bjoc.19.2

• electrochemistry is a highly economical tool that avoids chemical oxidants for synthesizing hypervalent iodine reagents [30]. Iodoarenes are suitable and well-established mediators in either in- or ex-cell electrochemical processes [31][32][33][34][35][36]. Nonetheless, HVIs, DIS and CDIS have been generated by

Iron-catalyzed domino coupling reactions of π-systems

• Austin Pounder and
• William Tam

Beilstein J. Org. Chem. 2021, 17, 2848–2893, doi:10.3762/bjoc.17.196

Cerium-photocatalyzed aerobic oxidation of benzylic alcohols to aldehydes and ketones

• Girish Suresh Yedase,
• Sumit Kumar,
• Jessica Stahl,
• Burkhard König and
• Veera Reddy Yatham

Beilstein J. Org. Chem. 2021, 17, 1727–1732, doi:10.3762/bjoc.17.121

• Br2, MnO2, hypervalent iodine reagents, chromium-based reagents, activated dimethyl sulfoxide, KMnO4, OsO4, or metal-based catalysts and peroxide were used [7][8][9][10][11][12][13][14][15][16][17]. Most of these protocols produce harmful waste and some of the oxidizing reagents are considered toxic

The biomimetic synthesis of balsaminone A and ellagic acid via oxidative dimerization

• Sharna-kay Daley and
• Nadale Downer-Riley

Beilstein J. Org. Chem. 2020, 16, 2026–2031, doi:10.3762/bjoc.16.169

• establish high-yielding and selective oxidative coupling reactions, has afforded new and greener synthetic protocols for biaryls [5][6][7]. Several oxidants, such as the salts of Ag(I&II) [8], Ti(III&IV) [9], Mn(III) [10], Ce(IV) [11], Sn(IV) [12] and Fe(III) [13], as well as the hypervalent iodine reagents

• aqueous conditions to prevent complexation of the reagent and the starting material. Of the Lewis acids used, stannic chloride proved to be the most effective oxidant for dimerization (Table 1). However, the hypervalent iodine reagents PIFA and PIDA gave better results overall, affording dimer 18 in 63

Copper-catalyzed O-alkenylation of phosphonates

• Nuria Vázquez-Galiñanes,
• Mariña Andón-Rodríguez,
• Patricia Gómez-Roibás and
• Martín Fañanás-Mastral

Beilstein J. Org. Chem. 2020, 16, 611–615, doi:10.3762/bjoc.16.56

• (alkenyl)iodonium salts, which are air- and moisture-stable, nontoxic and easy to prepare compounds, have become efficient reagents for mild and selective arylation and alkenylation reactions in organic synthesis [16][17][18]. In particular, the use of these hypervalent iodine reagents in copper catalysis

Construction of trisubstituted chromone skeletons carrying electron-withdrawing groups via PhIO-mediated dehydrogenation and its application to the synthesis of frutinone A

• Qiao Li,
• Chen Zhuang,
• Donghua Wang,
• Wei Zhang,
• Rongxuan Jia,
• Fengxia Sun,
• Yilin Zhang and
• Yunfei Du

Beilstein J. Org. Chem. 2019, 15, 2958–2965, doi:10.3762/bjoc.15.291

• high reaction temperature, extended reaction time, involvement of transition metal catalysts, and low yield. In these regards, the development of alternative approaches that can realize an efficient synthesis of chromones under mild conditions is desirable. In recent decades, hypervalent iodine

• reagents have emerged as a class of efficient and environmentally benign nonmetal “green” oxidants [66][67][68][69][70][71][72][73]. For instance, iodosobenzene (PhIO) [74] has been widely used in many synthetic transformations. It was found that PhIO is efficient in realizing epoxidation of olefins [75

Thermal stability of N-heterocycle-stabilized iodanes – a systematic investigation

• Andreas Boelke,
• Yulia A. Vlasenko,
• Mekhman S. Yusubov,
• Boris J. Nachtsheim and
• Pavel S. Postnikov

Beilstein J. Org. Chem. 2019, 15, 2311–2318, doi:10.3762/bjoc.15.223

• )cyclic iodanes. Albeit aryl-λ3-iodanes are viewed as safe and stable under ambient temperatures, systematic thermal degradation studies of hypervalent iodine reagents are still rare. In 1992 Varvoglis and co-workers investigated the thermal degradation of a variety of aryl iodine(III) dicarboxylates into

Synthesis of ([1,2,4]triazolo[4,3-a]pyridin-3-ylmethyl)phosphonates and their benzo derivatives via 5-exo-dig cyclization

• Aleksandr S. Krylov,
• Artem A. Petrosian,
• Julia L. Piterskaya,
• Nataly I. Svintsitskaya and
• Albina V. Dogadina

Beilstein J. Org. Chem. 2019, 15, 1563–1568, doi:10.3762/bjoc.15.159

• , hypervalent iodine reagents, etc. The synthetic methods towards diverse [1,2,4]triazolo[3,4-a]pyridines have been reviewed in detail [12][13]. It should be noted that the use of acetylene species to create this heterocycle (including triazole ring) is presented only by few examples. There has been reported

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

• Md Toufique Alam,
• Saikat Maiti and
• Prasenjit Mal

Beilstein J. Org. Chem. 2018, 14, 2396–2403, doi:10.3762/bjoc.14.216

• may take place between hypervalent iodine reagents and electron-rich amines. For this reason, synthetic methods based on hypervalent iodine reagents and primary amines under solvent-free conditions or constrained media are limited [8]. Recently, we have described a method for the successful reaction

Recent advances in hypervalent iodine(III)-catalyzed functionalization of alkenes

• Xiang Li,
• Pinhong Chen and
• Guosheng Liu

Beilstein J. Org. Chem. 2018, 14, 1813–1825, doi:10.3762/bjoc.14.154

• products. In addition, inorganic oxidants and peracetic acids can be used as oxidants as well. In 2005, the Ochiai and Kita groups demonstrated that m-chloroperbenzoic acid (mCPBA) was a better choice for the in situ generation of hypervalent iodine reagents through oxidation of iodoarenes [37][38]. Based

• rationalized by Woodward dioxolane intermediates (Scheme 3). Stereoselective dioxygenation using catalytic amounts of chiral hypervalent iodine reagents is a comparatively new area in hypervalent iodine chemistry. Fujita and co-workers described a stereoselective oxylactonization reaction in the presence of a

• first a nucleophilic attack from the vinylogous ester, then by the aromatic group, providing the final outcomes. Wirth and co-workers developed an oxidative rearrangement of alkenes to chiral α-aryl ketones, in which electron-deficient chiral lactic acid-based hypervalent iodine reagents were

Synthesis of spirocyclic scaffolds using hypervalent iodine reagents

• Fateh V. Singh,
• Priyanka B. Kole,
• Saeesh R. Mangaonkar and
• Samata E. Shetgaonkar

Beilstein J. Org. Chem. 2018, 14, 1778–1805, doi:10.3762/bjoc.14.152

• Fateh V. Singh Priyanka B. Kole Saeesh R. Mangaonkar Samata E. Shetgaonkar Chemistry Division, School of Advanced Sciences (SAS), VIT University, Chennai Campus, Chennai-600 127, Tamil Nadu, India 10.3762/bjoc.14.152 Abstract Hypervalent iodine reagents have been developed as highly valuable

• reagents in synthetic organic chemistry during the past few decades. These reagents have been identified as key replacements of various toxic heavy metals in organic synthesis. Various synthetically and biologically important scaffolds have been developed using hypervalent iodine reagents either in

• stoichiometric or catalytic amounts. In addition, hypervalent iodine reagents have been employed for the synthesis of spirocyclic scaffolds via dearomatization processes. In this review, various approaches for the synthesis of spirocyclic scaffolds using hypervalent iodine reagents are covered including their

Glycosylation reactions mediated by hypervalent iodine: application to the synthesis of nucleosides and carbohydrates

• Yuichi Yoshimura,
• Hideaki Wakamatsu,
• Yoshihiro Natori,
• Yukako Saito and
• Noriaki Minakawa

Beilstein J. Org. Chem. 2018, 14, 1595–1618, doi:10.3762/bjoc.14.137

• glycosylation of the sulfoxide 32 could be performed in the same flask, the reaction could bypass two of the reaction steps and would directly produce 4’-thionucleoside 35 from 31. Indeed, the utilization of hypervalent iodine would have enabled this short-cut reaction (Figure 2). Hypervalent iodine reagents

• reported by Kita and co-workers [44]. Their paper prompted Nishizono et al. to study the glycosylation reaction for 4’-thionucleosides using hypervalent iodine reagents. As a 4-thiosugar donor, 2-p-methoxybenzoate derivative 36 was prepared following Matsuda’s method as shown in Scheme 2, and then was

• reaction of 36 with iodosylbenzene (PhI=O) proceeded stereoselectively and gave only the β-anomer of 37 in 53% yield [45] (Scheme 4). The mechanism of hypervalent iodine-mediated glycosylation can be expressed as shown in Figure 3. The activated hypervalent iodine reagents in the presence of TMSOTf reacted