Reactivities of novel [hydroxy(tosyloxy)iodo]arenes and [hydroxy(phosphoryloxy)iodo]arenes for alpha-tosyloxylation and alpha-phosphoryloxylation of ketones

Novel [hydroxy(tosyloxy)iodo]arenes bearing 2-thienyl, 3-thienyl, N-tosyl-4-pyrazolyl, 3-trifluoromethylphenyl, and 3,5-bis(trifluoromethy)phenyl as an aromatic group, and [hydroxy(phosphoryloxy)iodo]arenes bearing N-tosyl-4-pyrazolyl, 3-trifluoromethylphenyl, and 3,5-bis(trifluoromethy)phenyl as an aromatic group, were prepared. alpha-Tosyloxylation and alpha-phosphoryloxylation of ketones with these compounds were carried out, respectively. Their reactivities were compared with that of the parent [hydroxy(tosyloxy)iodo]benzene and [hydroxy(phosphoryloxy)iodo]benzene, respectively, and consequently [hydroxy(tosyloxy)iodo]arenes and [hydroxy(phosphoryloxy)iodo]arenes bearing 3-trifluoromethylphenyl and 3,5-bis(trifluoromethy)phenyl as an aromatic group showed the best reactivity. These new compounds can be used as powerful alpha-tosyloxylation and alpha-phosphoryloxylation reagents, instead of the parent [hydroxy(tosyloxy)iodo]benzene and [hydroxy(phosphoryloxy)iodo]benzene.     

Facile synthesis of Koser's reagent and derivatives from iodine or aryl iodides

The first one-pot synthesis of neutral and electron-rich [hydroxy(tosyloxy)iodo]arenes (HTIBs) from iodine and arenes is presented, thereby avoiding the need for expensive iodine(III) precursors. A large set of HTIBs, including a polyfluorinated analogue, can be obtained from the corresponding aryl iodide under the same conditions. The reaction proceeds under mild conditions, without excess reagents, and is fast and high-yielding. Together, the two presented routes give access to a wide range of HTIBs, which are useful reagents in a variety of synthetic transformations.     

Novel preparation of 2,1-benzothiazine derivatives from sulfonamides with [hydroxy(tosyloxy)iodo]arenes

Cyclization of sulfonamides bearing an aromatic ring at the beta-position with various organohypervalent iodine compounds was carried out to form the corresponding 2,1-benzothiazine derivatives. Among them, the cyclization effectively proceeded with [hydroxy(tosyloxy)iodo]arenes through ionic pathways. The same treatment of a sulfonamide bearing a 4-methoxyphenyl group at the beta-position generated a spiro compound.     

Oxidative azacyclization of 1-monosubstituted thioureas in reaction with [bis(acyloxy)iodo]arenes to form 1,2,4-thiadiazole derivatives

For the first time, derivatives of 1,2,4-thiadiazoles have been obtained by the reaction of [bis(acyloxy)iodo]arenes with 1-monosubstituted thioureas. 1-Acetylthiourea is subject to intermolecular azacyclization to form 3,5-bis-(acetylamino)-1,2,4-thiadiazole in reaction with [bis(acyloxy)iodo]benzene. 1-Phenylthiourea forms 3,5-bis-(phenylamino)-1,2,4-thiadiazole in a single-stage reaction with (diacetoxyiodo)benzene. The reaction of 1-phenylthiourea with [bis(trifluoroacetoxy)iodo]benzene leads to the formation of 5-imino-4-phenyl-3-phenylamino-4H-1,2,4-thiadiazoline.     

One‐Pot Synthesis of α‐Formyloxy Ketones from Enolizable Ketones

One‐pot synthesis of α‐formyloxy tones as well as α‐acetoxy ketones from enolizable ketones and [hydroxy(tosyloxy) iodo] benzene (HTIB)/polymer supported [hydroxy(tosyloxy) iodo] benzene (PSHTIB) in N,N–dimethylformamide (DMF)/N, N–dimethylacetamide (DMA) in high yields is described.     

Hypervalent Iodine in Synthesis XXIII: Oxidation with [Hydroxy(tosyloxy)iodo]benzene: Selective Oxidation of Sulfides to Sulfoxides

Alkyl-and aryl-sulfides can be selectively oxidated to their corresponding sulfoxides with excellent yields under mild conditions by [hydroxy (tosyloxy)iodo]benzene. Morever, [hydroxy (((+)-10-camphorosulfonyl)oxy)iodo]benzene as the chiral oxidizer, can be used to oxidate unsymmetric sulfides to sulfoxides with a few %ee to some extent.     

Efficient oxidation of benzylic alcohols with [hydroxy(tosyloxy)iodo]benzene under microwave irradiation

An efficient method for the oxidation of benzylic alcohols with [hydroxy(tosyloxy)iodo]benzene under solvent-free microwave irradiation conditions is described.     

Preparation and X-ray structures of 3-[Bis(trifluoroacetoxy)iodo]benzoic acid and 3-[hydroxy(tosyloxy)iodo]benzoic acid: new recyclable hypervalent iodine reagents

Preparation, structural characterization, and reactivity of 3-[bis(trifluoroacetoxy)iodo]benzoic acid and 3-[hydroxy(tosyloxy)iodo]benzoic acid, new recyclable iodine(III) reagents derived from 3-iodosylbenzoic acid, are described. The reduced form of these reagents, 3-iodobenzoic acid, can be easily recovered from the reaction mixtures using ion-exchange resin or basic aqueous workup followed by acidification with HCl.     

Synthesis of spirodienones by intramolecular ipso-cyclization of N-methoxy-(4-halogenophenyl)amides using [hydroxy(tosyloxy)iodo]benzene in trifluoroethanol

Spirodienones bearing the 1-azaspiro[4.5]decane ring system have been synthesized from N-methoxy-(4-halogenophenyl)amides by the intramolecular ipso attack of a nitrenium ion generated with [hydroxy(tosyloxy)iodo]benzene in trifluoroethanol.     

Desymmetrized Leaning Pillar[6]arene

In this work, a novel version of macrocyclic arenes, namely leaning pillar[6]arenes, was discovered and it can be considered as a tilted version of a pillar[6]arene with two hydroxy/alkoxy functionalities removed. Through a facile two‐step synthetic approaches, in conjunction with a diversity of post‐modification possibilities, a series of leaning pillar[6]arenes, with good cavity adaptability and enhanced guest‐binding capability, was synthesized, and their self‐assembly in single‐crystal states is presented. DFT calculations demonstrated that the lower rotational barrier of unsubstituted phenylene rings, the uneven electron density centered at the leaning phenyl rings, and the polarization effect along the edge generated by the hydrogen‐bond‐induced orientation of hydroxy groups greatly affected the host‐guest properties, and meanwhile provided an intuitive explanation for the pillar‐like and rigid structure of traditional pillar[6]arenes. Significantly, the crystal structure of cyclo‐oligomeric quinone was obtained by direct oxidation of leaning pillar[6]arenes.     

Biphenyl- and terphenyl-based recyclable organic trivalent iodine reagents

Biphenyl- and terphenyl-based recyclable trivalent iodine reagents, such as 4-bromo-4′-(diacetoxyiodo)biphenyl, 4,4′-bis(diacetoxyiodo)biphenyl, 1,4-bis[4-(diacetoxyiodo)phenyl]benzene, 4-bromo-4′-[(hydroxy)(tosyloxy)iodo]biphenyl, 4,4′-bis[(hydroxy)(tosyloxy)iodo]biphenyl, were simply prepared and their reactivities for the oxidative rearrangement of ketones to esters, TEMPO-mediated oxidation of alcohols to aldehydes or ketones, oxidative dealkylation of N-alkylsulfonamides to sulfonamides, and α-tosyloxylation of ketones were compared with p-(diacetoxyiodo)toluene and p-[(hydroxy)(tosyloxy)iodo]toluene to show the same reactivities and, moreover, the biphenyl- and terphenyl-based iodoarenes formed were recovered by simple filtration of the reaction mixture in every reaction. Thus, these biphenyl- and terphenyl-based trivalent iodine reagents can be used as the recyclable reagents.     

Calix[4]arenes bearing α‐amino‐ or α‐hydroxyphosphonic acid fragments at the upper rim

By the reaction of para‐formylcalix[4]arenes 1–6 with trialkyl phosphites in the presence of dry hydrogen chloride, calix[4]arenes 7–13 possessing dialkylphosphoryl‐hydroxymethyl groupings at the upper rim were synthesized. Calix[4]arenes 18–23 functionalized with dialkylphosphoryl‐alkyl(aryl)aminomethyl groups were obtained by sodium‐promoted addition of dialkyl phosphites to C=N bonds of para‐iminocalix[4]arenes 14–17 . The consecutive treatment of α‐hydroxy‐ or α‐aminophosphonic acid dialkyl esters of calix[4]arenes 7, 10, 18 , and 21 with bromotrimethylsilane and methanol gave dihydroxyphosphoryl derivatives of calix[4]arenes 24–27 . It was shown that calix[4]arenes bearing at the macrocyclic upper rim hydroxymethylphosphonic fragments, as well as bis‐hydroxymethyl(aminomethyl)phosphonic fragments, are able to undergo self‐assembly with formation of dimeric OH···O=P hydrogen bonded associates. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:58–67, 2001     

Efficient microwave induced direct α-halogenation of carbonyl compounds

A novel and direct method for the synthesis of α-halocarbonyl compounds using sequential treatment of carbonyl compounds with [hydroxy(tosyloxy)iodo]benzene followed by magnesium halides under solvent-free microwave irradiation conditions is described.     

Solvent-free facile synthesis of novel α-tosyloxy β-keto sulfones using [hydroxy(tosyloxy)iodo]benzene

A facile, general and high yielding protocol for the synthesis of novel α-tosyloxy β-keto sulfones is described utilizing relatively non-toxic, [hydroxy(tosyloxy)iodo]benzene, under solvent-free conditions at room temperature.     

Oxidative rearrangements of arylalkenes with [hydroxy(tosyloxy)iodo]benzene in 95% methanol: a general, regiospecific synthesis of α-aryl ketones

The treatment of arylalkenes with [hydroxy(tosyloxy)iodo]benzene in 95% methanol affords the corresponding α-aryl ketones. This oxidative rearrangement is general for acyclic and cyclic arylalkenes and permits regioselective syntheses of isomeric α-phenyl ketone pairs.     

5-烃基-5-对甲苯磺酰氧基丙二酸亚异丙酯的合成

报道了利用羟基(对甲苯磺酰氧基)碘苯与5-烃基丙二酸亚异丙酯的反应合成5-烃基-5-对甲苯磺酰氧基丙二酸亚异丙酯的方法。提出了该反应的可能机理。     

Selective Oxidation of Sulfides to Sulfoxides With Poly[4‐Hydroxy(tosyloxy)iodo]styrene

Sulfides can be selectively converted to corresponding sulfoxides in excellent yields under mild conditions by linear and 1% cross‐linked poly[4‐hydroxy(tosyloxy)iodo]styrene (PSHTIB).     

A Facile [hydroxy(tosyloxy)iodo]benzene Mediated Synthesis of Symmetrical Triazolo-[3,4-b]-1,3,4-Thiadiazines

Synthesis of the title compounds has been accomplished by a one-pot procedure involving the reaction of 3-substituted-4-amino-5-mercapto-1,2,4-triazoles and a variety of heterocyclic ketones in the presence of [hydroxy(tosyloxy)iodo]benzene.     

Synthesis of All‐Carbon Disubstituted Bicyclo[1.1.1]pentanes by Iron‐Catalyzed Kumada Cross‐Coupling

1,3‐Disubstituted bicyclo[1.1.1]pentanes (BCPs) are important motifs in drug design as surrogates for p‐substituted arenes and alkynes. Access to all‐carbon disubstituted BCPs via cross‐coupling has to date been limited to use of the BCP as the organometallic component, which restricts scope due to the harsh conditions typically required for the synthesis of metallated BCPs. Here we report a general method to access 1,3‐C‐disubstituted BCPs from 1‐iodo‐bicyclo[1.1.1]pentanes (iodo‐BCPs) by direct iron‐catalyzed cross‐coupling with aryl and heteroaryl Grignard reagents. This chemistry represents the first general use of iodo‐BCPs as electrophiles in cross‐coupling, and the first Kumada coupling of tertiary iodides. Benefiting from short reaction times, mild conditions, and broad scope of the coupling partners, it enables the synthesis of a wide range of 1,3‐C‐disubstituted BCPs including various drug analogues.     

[Hydroxy(tosyloxy)iodo]benzene: A Tosyloxylating Agent with Selectivity for Ketones in the Reactions with Benzalacetones

The treatment of enolizable ketones containing a conjugated double bond, namely benzalacetones with [hydroxy(tosyloxy)iodo]benzene, leads to regioselective tosyloxylation, thereby giving new compounds (α-tosyloxybenzalacetones).