Pyridinium o-iodoxybenzoate as a Safe form of a Famous Oxidant

The stable pyridinium salt of o-iodoxybenzoic acid (PIBX) that is easy to obtain can serve as a convenient substitute of IBX as an oxidant. PIBX is safer, has neutral properties behaves as an equivalent to IBX in the oxidation of alcohols to ketones or aldehydes in polar solvents (DMF, DMSO), and provides higher oxidation rate in THF due to better solubility.     

A stabilized formulation of IBX (SIBX) for safe oxidation reactions including a new oxidative demethylation of phenolic methyl aryl ethers

[reaction: see text] SIBX is a nonexplosive formulation of IBX that can be used as a suspension in a variety of standard organic solvents such as refluxing EtOAc and THF to oxidize safely alcohols into aldehydes and ketones. The use of hot THF is limited to the oxidation of allylic and benzylic alcohols. Most yields are comparable to those obtained with IBX or DMP. SIBX can also be used to perform oxygenative demethylation of 2-methoxyarenols into orthoquinones and catechols.     

2-Methyl-2-propanol as solvent for o-iodoxybenzoic acid (IBX) oxidation of 1? alcohols to aldehydes

2-Methyl-2-propanol has been demonstrated to be an effective solvent for IBX oxidation of 1? alcohols to the corresponding aldehydes. IBX has a measurable, but low, solubility in 2-methyl-2-propanol and thus partially avoids the drawbacks inherent in the solubility problems associated with IBX without resorting to less desirable solvents. This may be particularly useful where solubility of the alcohol is also at issue.     

Simple preparation of polymer supported IBX esters and amides and their oxidative properties

Novel polymer supported IBX esters and amides were prepared in two steps, which were the coupling of 2-iodobenzoic acid to a hydroxy or amino polystyrene followed by activation of the intermediate product. These polymer supported reagents were tested as oxidants by the conversion of a series of alcohols to the corresponding aldehydes or ketones. We found that the polymer supported IBX amides displayed excellent oxidative activity, in that they oxidized benzyl alcohol to benzaldehyde completely within 1 h at an oxidant to alcohol ratio of 2 to 1.     

Modified o-methyl-substituted IBX: room temperature oxidation of alcohols and sulfides in common organic solvents

o-Methyl-substituted Me-IBX is the first modified analog of IBX that oxidizes alcohols in common organic solvents at room temperature, due to a composite of two factors, that is, low solubility and hypervalent twisting-promoted rate enhancement. Furthermore, the reagent is efficient for selective oxidation of sulfides to sulfoxides, a transformation that otherwise occurs only sluggishly with standard IBX. The facile synthetic accessibility and its mild as well as non-hazardous nature render Me-IBX a stable equivalent of Dess-Martin periodinane reagent in organic oxidations.     

In situ generation of o-iodoxybenzoic acid (IBX) and the catalytic use of it in oxidation reactions in the presence of Oxone as a co-oxidant

[structure: see text] Catalytic use of o-iodoxybenzoic acid (IBX) in the presence of Oxone as a co-oxidant is demonstrated for the oxidation of primary and secondary alcohols in user- and eco-friendly solvent mixtures. Also demonstrated is the in situ (re)oxidation of 2-iodosobenzoic acid (IBA) and even commercially available 2-iodobenzoic acid (2IBAcid) by Oxone to IBX allowing one to use these less hazardous reagents, in place of potentially explosive IBX, as catalytic oxidants.     

Enhancing 2-iodoxybenzoic acid reactivity by exploiting a hypervalent twist

A rearrangement of hypervalent bonds, or twisting, proves to be the rate-determining step in the 2-iodoxybenzoic acid (IBX) oxidation of alcohols. From this insight, derived from density functional theory calculations, we explain why IBX oxidizes large alcohols faster than small ones and propose a modification to the reagent predicted to make it more active.     

Studies on oxidations with IBX: oxidation of alcohols and aldehydes under solvent-free conditions

A variety of allylic and benzylic alcohols are oxidized to their respective carbonyl compounds with IBX under solvent-free conditions at ca. 60-70 °C. It has also been found that some of the aromatic aldehydes also undergo oxidation when heated with IBX at 90 °C under solvent-free conditions; notably, this transformation does not occur under the otherwise identical but heterogeneous conditions.     

Mild oxidation of alcohols with o-iodoxybenzoic acid (IBX) in water/acetone mixture in the presence of beta-cyclodextrin

A mild and efficient oxidation of alcohols with o-iodoxybenzoic acid (IBX) catalyzed by beta-cyclodextrin in a water/acetone mixture (86:14) has been developed. A series of alcohols were oxidized at room temperature in excellent yields.     

6-Membered pseudocyclic IBX acids: syntheses, X-ray structural characterizations, and oxidation reactivities in common organic solvents

We designed and synthesized λ(5)-cyclic periodinanes 1 and 2, which are homologous to IBX (1-hydroxy-1-oxo-1H-1λ(5)-benzo[d][1,2]iodoxol-3-one) by one carbon, to thwart close packing of molecules in the crystal lattice to permit solubility in common organic solvents and to facilitate oxidations with enhanced reactivity. The X-ray crystal structures revealed that both 1 and 2 exist in the solid state as pseudocyclic (PC) acids, i.e., 1PC and 2PC, and that the molecules in the lattice are less weakly associated as compared to those in the parent IBX due to the twisting introduced via the sp(3) benzylic carbon. Both 1PC and 2PC are found to dissolve in palpable amounts in DCM and acetonitrile to allow oxidation of a variety of alcohols and sulfides to carbonyl compounds and sulfoxides in a facile manner. The subtle differences in the sterics due to methyl and ethyl substituents in 1PC and 2PC are found to manifest in contrasting reactivities in that the oxidations of alcohols occur faster with 2PC, while those of sulfides to sulfoxides occur more rapidly with 1PC.     

A facile route to a polymer-supported IBX reagent

A three-step preparation of a polymer-supported IBX reagent from poly(p-methylstyrene) is reported. This reagent has been used successfully for the efficient oxidation of a series of alcohols to the corresponding aldehydes.     

2-碘酰基苯甲酸(2-Iodoxybenzoic acid, IBX)在有机合成中的应用

综述了近年来2-碘酰基苯甲酸(2-iodoxybenzoic acid, IBX)在有机合成中的应用, 重点评述了IBX对醇类、含氮有机物、含硫有机物、连接在芳环上的碳原子的氧化反应, 探讨了IBX在α,β-不饱和羰基化合物和内酯合成中的应用, 这些反应具有反应条件温和、产率高、选择性好等优点. 简单介绍了IBX的一些新衍生物的合成及应用.     

A simple and advantageous protocol for the oxidation of alcohols with O-iodoxybenzoic acid (IBX)

[reaction: see text] An efficient, user-friendly procedure for the oxidation of alcohols using IBX is described. Simply heating a solution of the alcohol in the presence of suspended IBX followed by filtration and removal of the solvent gives excellent yields of the corresponding carbonyl compounds. We illustrate this procedure with a panel of primary and secondary alcohol substrates and note that it allows recycling and reuse of the oxidant.     

2-Iodoxybenzoic acid--a simple oxidant with a dazzling array of potential applications

Since its discovery by Christoph Hartmann and Victor Meyer in 1893, 2-iodoxybenzoic acid (IBX) has emerged as a rather ubiquitous oxidant for organic synthesis. The past decade has seen the development of a large variety of applications that go far beyond the simple oxidation of alcohols. This Review is concerned with the synthetic potential of IBX, with particular emphasis on uncommon reactivity patterns and novel fields of application.     

A simple method for the oxidation of primary alcohols with o-iodoxybenzoic acid (IBX) in the presence of acetic acid

A simple method for the oxidation of primary alcohols to aldehydes using o-iodoxybenzoic acid (IBX) with the addition of stoichiometric acetic acid has been developed. Addition of acetic acid significantly accelerated the reaction rate. Under these conditions, primary aliphatic, benzylic, and allylic alcohols are smoothly converted to aldehydes in high yields (90-97%).     

Mild oxidation of alcohols with O-iodoxybenzoic acid (IBX) in ionic liquid 1-butyl-3-methyl-imidazolium chloride and water

[reaction: see text] A mild, efficient, and eco-friendly procedure for the oxidation of alcohols with IBX in ionic liquid [bmim]Cl and water has been developed. Simply stirring of a solution of the alcohol and IBX in [bmim]Cl/water at room temperature followed by extraction with ether or ethyl acetate and removal of the solvent gives excellent yields of the corresponding carbonyl compounds. Recycling and reuse of the oxidant and ionic liquid have also been reported.     

The oxidation of alcohols with O-iodoxybenzoic acid (IBX) in aqueous nanomicelles at room temperature

GMPGS-2000, a nonionic amphiphile composed of Guerbet alcohol (2-octyldodecan-1-ol), MPEG-2000 and succinic acid, has been prepared as an effective nanomicelle forming species for the oxidation of alcohols with 2-iodoxybenzoic acid (IBX) in water at room temperature.     

Facile conversion of lactols to lactones using IBX

Lactols, which are insoluble or only sparingly soluble in most of the organic solvents that are generally employed for oxidation, are converted to lactones using o-iodoxybenzoic acid (IBX) in a facile manner under modified experimental conditions [EtOAc-DMSO (9:1) mixture at reflux] in good to excellent isolated yields (66-91%).     

Epoxidation and oxidation reactions using 1,4-butanediol dimethacrylate crosslinked polystyrene-supported tertiary butyl hydroperoxide

1,4-Butanediol dimethacrylate (1,4-BDDMA) crosslinked polystyrene-supported t-butyl hydroperoxide was employed in the epoxidation of olefins and oxidation of alcohols to carbonyl compounds. The reagent proved to be successful as a recyclable solid phase organic reagent with as much or more efficiency when compared to its monomeric counterpart. The extent of reaction was found to be dependent on various reaction parameters like solvent, temperature, molar concentration and presence of catalyst.     

The first one-pot oxidative 1,2-acetoxysulfenylation and 1,2-disulfenylation of Baylis-Hillman alcohols in an ionic liquid

The first example of tandem oxidation and 1,2-acetoxysulfenylation/1,2-disulfenylation of Baylis-Hillman (BH) alcohols to afford 1,2-acetoxysulfides/1,2-dithioethers is reported. The reaction involves oxidation of BH alcohols with IBX in [bmim]Br to give β-ketomethylene compounds in situ followed by CuI-imidazole-catalyzed 1,2-acetoxysulfenylation with an organodisulfide and acetic acid under air to afford vicinal acetoxysulfides in excellent yields with complete regioselectivity. In the absence of the Cu(I) catalyst, 1,2-disulfenylation takes place to give vicinal dithioethers in 81-90% yields.