東郷 秀雄

A bromo-lactonization of alkenyl carboxylic acids and a bromo-cyclization of N-allyl amides as oxygen-nucleophilic bromo-cyclization reactions were developed via the oxidative umpolung of bromide using alkali metal bromide and inorganic oxidant to provide the corresponding cyclization products in high yields. In particular, the use of AcOEt, the solvent of choice for green sustainable reactions, led to the high reactivities of the present reactions. This methodology is highly recommended for green sustainable chemistry because it uses stable and non-hazardous reagents instead of other bromo reagents and oxidants, and does not produce organic wastes that pollute the environment.

A variety of 2-arylbenzofurans were obtained in good yields by the O-arylation of oximes with diaryliodonium triflates, followed by the treatment with HCl in dioxane under warming conditions through the [3,3]-sigmatropic reaction. The present reaction is one-pot transition metal-free method for the preparation of various 2-arylbenzofurans from oximes, which are easily available from the reaction of alkyl aryl ketones with hydroxylamine

The treatment of phenols with paraformaldehyde in the presence of MgCl2 and Et3N in THF at 80 degrees C, followed by reaction with molecular iodine and aq. ammonia at room temperature provided the corresponding o-cyanophenols in moderate to good yields. The present reaction is a one-pot transformation of phenols into o-cyanophenols using much less expensive reagents than are typically used; the reaction is free of both transition-metals and cyanide. The utility of this reaction was highlighted during our preparation of Febuxostat from p-bromophenol.

Various methylarenes were transformed into the corresponding aromatic nitriles in good to moderate yields by the treatment with aq. HBr and aq. H2O2, followed by reaction with molecular iodine and aq. ammonia in a one-pot procedure. The present reaction is a useful, practical, transition-metal-free, and organic-reagent-free method for the preparation of aromatic nitriles from methylarenes.

A bromide-catalyzed oxidation of alcohols was developed which proceeded in the presence of an alkali metal bromide and an oxidant under mild conditions. The reaction involved an organic-molecule-free oxidation using KBr and Oxone and a Bronsted acid assisted oxidation using KBr and aqueous H2O2 solution to provide a broad range of carbonyl compounds in high yields. Moreover, the bromide-catalyzed oxidation of primary alcohols enabled the divergent synthesis of carboxylic acids and aldehydes under both reaction conditions in the presence of TEMPO. A possible catalytic mechanism was suggested on the basis of various mechanistic studies.

The oxidative debenzylation of N-benzyl amides and O-benzyl ethers was promoted with high efficiency by a bromo radical formed through the oxidation of bromide from alkali metal bromide under mild conditions. This reaction provided the corresponding amides from N-benzyl amides and carbonyl compounds from O-benzyl ethers in high yields.

On the basis of studies of the transformation of benzylic bromides into the corresponding aromatic aldehydes by treatment with N-methylmorpholine N-oxide, various methylarenes were treated either with DBDMH in the presence of AIBN in acetonitrile at reflux (Method A) or with NBS in CCl4 under irradiation with a tungsten lamp at 30 degrees C (Method B), followed by treatment with N-methylmorpholine N-oxide to provide aromatic aldehydes in good yields. These methods could be adopted in one-pot transformations of methylarenes into aromatic aldehydes under conditions free of less toxic reagents and transition metals.

The reaction of terminal alkynes with n-BuLi, and then with aldehydes, followed by the treatment with molecular iodine, and subsequently hydrazines or hydroxylamine provided the corresponding 3,5-disubstituted pyrazoles or isoxazoles in good yields with high regioselectivity, through the formations of propargyl secondary alkoxides and alpha-alkynyl ketones. The present reactions are one-pot preparation of 3,5-disubstituted pyrazoles from terminal alkynes, aldehydes, molecular iodine, and hydrazines, and 3,5-disubstituted isoxazoles from terminal alkynes, aldehydes, molecular iodine, and hydroxylamine.

Various benzylic and aliphatic alcohols were smoothly oxidized to the corresponding aromatic aldehydes and ketones as well as aliphatic ketones by treatment with 1-acetoxy-5-nitro-1,2-benziodoxole-3(1H)-one (ANBX), 1-acetoxy-5-bromo-1,2-benziodoxole-3(1H)-one (ABBX), 1-acetoxy-5-chloro-1,2-benziodoxole-3(1H)-one (ACBX), and 1-acetoxy-5-fluoro-1,2-benziodoxole-3(1H)-one (AFBX). These new trivalent iodine compounds were prepared from 5-substituted 2-iodobenzoic acids and meta-chloroperoxybenzoic acid (m-CPBA). ANBX and ABBX were the most effective reagents for this oxidation of alcohols, and this present reaction is very attractive because of the ease of product isolation and the reusability of the reagents.

A variety of aryl bromides have been treated with Mg and then chloral, followed by tBuOCl and subsequently alcohols or amines to produce the corresponding aromatic esters or amides in good yields via the formation of aryl trichloromethyl ketones as intermediates. These reactions are examples of a transition-metal-free one-pot preparation of aromatic esters and amides from aryl bromides.

A variety of aromatic and aliphatic carboxylic acids were smoothly converted into the corresponding nitriles in good yields in a one-pot procedure by treatment with ethyl iodide/K2CO3/18-crown-6, followed by sodium diisobutyl-tert-butoxyaluminium hydride (SDBBA-H), and finally treatment with molecular iodine or 1,3-diiodo-5,5-dimethylhydantoin (DIH), and aqueous ammonia. This method is useful for the conversion of various aromatic and aliphatic carboxylic acids into the corresponding nitriles in a one-pot procedure.

A variety of methylarenes were successfully converted into the corresponding aromatic nitriles in good to moderate yields by the treatment with NBS or DBDMH in the presence of a catalytic amount of AIBN or BPO, followed by the reaction with molecular iodine in aq NH3 in a one-pot procedure. The present reaction is a useful and practical transition-metal-free method for the preparation of aromatic nitriles from methylarenes. © 2013 American Chemical Society.

Various benzylic and primary alcohols were efficiently converted into the corresponding nitriles in good yields at room temperature by treatment with tert-butyl hypochlorite, diiodine, or 1,3-diiodo-5,5-dimethylhydantoin in the presence of (2,2,6,6-tetramethylpiperidin-1-yl) oxidanyl (TEMPO), followed by treatment with diiodine and aqueous ammonia. The nitriles were obtained in good yields and high purities simply by extraction of the reaction mixture with chloroform and subsequent removal of the solvent.

Various benzylic alcohols and aliphatic secondary alcohols were smoothly oxidized to the corresponding aromatic aldehydes, aromatic ketones, and aliphatic ketones, respectively, with the novel 1-acetoxy-5-nitro-1,2-benziodoxole-3(1H)-one (ANBX) alone, a trivalent iodine prepared from the oxidation of 2-iodo-5-nitrobenzoic acid with MCPBA. The present reaction is the first effective method for the oxidation of alcohols with a trivalent iodine alone under mild reaction conditions.

Ion-supported Ph3P, 4-(diphenylphosphino)benzyltrimethylammonium bromide (IS-Ph3P), could be used for the facile amidation of a wide range of carboxylic acids with amines in the presence of bromotrichloromethane to provide the corresponding amides in good yields. In the present reaction, the desired amides were obtained in good yields with high purity by simple extraction of the reaction mixture with diethyl ether or chloroform and subsequent removal of the solvent from the extract. Moreover, ion-supported Ph3PO (IS-Ph3PO), which was a co-product derived from IS-Ph3P in the present reductive condensation, was recovered in high yield and could be reduced to IS-Ph3P for reuse in the same amidation of carboxylic acid. (C) 2013 Elsevier Ltd. All rights reserved.

The oxidation of secondary alcohols and primary alcohols with two novel ion-supported (diacetoxyiodo)benzenes (IS-DIBs) A and B in the presence of a catalytic amount of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) in dichloromethane at room temperature proceeded efficiently to provide the corresponding ketones and aldehydes, respectively, in good yields. The oxidative reaction of N,N-diisopropylbenzylamines with those IS-DIBs was also carried out to generate the corresponding aromatic aldehydes in good yields. In addition, the Hofmann rearrangement of primary amides in methanol under basic conditions and the oxidative 1,2-rearrangement of propiophenones in trimethyl orthoformate under acidic conditions with those IS-DIBs provided the corresponding methyl carbamates and methyl 2-arylpropanoates, respectively, in good yields. Moreover, treatment of acetophenones with those IS-DIBs in the presence of trifluoromethanesulfonic acid in acetonitrile generated the corresponding 5-aryl-2-methyloxazoles in good yields. In those five reactions, the desired products were obtained in good yields with high purity by simple extraction of the reaction mixture with diethyl ether and subsequent removal of the solvent from the extract. Moreover, ion-supported iodobenzenes, which were the co-products derived from IS-DIBs in the present oxidative reactions, were recovered in good yields and could be re-oxidized to IS-DIBs A and B for reuse in the same oxidative reactions. (C) 2013 Elsevier Ltd. All rights reserved.

Various aryl bromides were efficiently converted into the corresponding aromatic nitriles in good yields by the treatment with Mg turnings and subsequently DMF, followed by treatment with molecular iodine and aq NH3. The same treatment of aryl bromides, which are weakly reactive to Mg turnings, with (PrMgCl)-Pr-i.LiCl and subsequently DMF, followed by the treatment with molecular iodine and aq NH3 also afforded the corresponding aromatic nitriles in good yields. On the other hand, when N-formylpiperidine was used instead of DMF, p-substituted beta-bromostyrenes were converted into the corresponding p-substituted cinnamonitriles, i.e., alpha,beta-unsaturated nitriles, in good to moderate yields by the same procedure. The reactions were carried out by means of a simple experimental procedure and did not require any toxic metal cyanides or expensive rare metals. Therefore, the present reactions are practical and environmentally benign one-pot methods for the preparation of aromatic nitriles, cinnamonitriles, and aliphatic nitriles from aryl bromides, beta-bromostyrenes, and alkyl bromides, respectively, through the formation of Grignard reagents and their DMF or N-formylpiperidine adducts. (C) 2012 Elsevier Ltd. All rights reserved.

Unsymmetrical diaryl ethers were efficiently obtained in good yields by the reactions of aryl(4-methoxyphenyl)iodonium tosylates with phenols, and aryl(2,4-dimethoxyphenyl)iodonium tosylates with phenols, in the presence of potassium carbonate in acetonitrile, respectively. The latter iodonium tosylates provided the corresponding unsymmetrical diaryl ethers in good yields with high regioselectivities, together with the quantitative formation of 1-iodo-2,4-dimethoxybenzene.

The intramolecular aminohydroxylation of N-alkenylsulfonamides proceeded under heavy metal-free conditions to give substituted prolinol derivatives in high yields. Oxone activated by catalytic Bronsted acid worked well as an electrophilic oxidant for this reaction.

Various [(diacetoxy)iodo]arenes bearing 4-methylphenyl, phenyl, 4-nitrophenyl, 3-nitrophenyl, 4-cyanophenyl, 4-bromophenyl, 4-methoxycarbonyphenyl, 3,5-bis(trifluoromethyl)phenyl, and 4-(N,N,N-trimethylammonium)methylphenyl groups were efficiently prepared by the treatment of iodoarenes with m-chloroperoxybenzoic acid in acetic acid. The great advantage of the present method is the easy preparation and isolation of [(diacetoxy)iodo] arenes bearing electron-withdrawing groups, such as 4-nitro, 4-cyano, 4-methoxycarbonyl, and 3,5-bis(trifluoromethyl) groups, on the aromatic ring.

Various diaryl ketones, alkyl aryl ketones, and dialkyl ketones were efficiently prepared in good yields by the reactions of the Grignard reagents derived from aryl or alkyl bromides, followed by the reactions with aromatic or aliphatic aldehydes and the subsequent treatment with 1,3-diiodo-5,5-dimethylhydantoin and K2CO3, in a one-pot method. The same treatment of aromatic bromides bearing electron-withdrawing groups, such as ester, nitrile, ketone, and nitro groups with i-PrMgCl center dot LiCl or PhMgCl instead of Mg, also provided the corresponding diaryl and alkyl aryl ketones in good yields. The above methods are simple and practical transition-metal-free methods for the preparation of various diaryl ketones and alkyl aryl ketones bearing electron-rich aromatic groups and electron-deficient aromatic groups, as well as dialkyl ketones. (C) 2012 Elsevier Ltd. All rights reserved.

The Swern oxidation of various benzylic and allylic alcohols, primary alcohols, and secondary alcohols with two ion-supported methyl sulfoxides A-1 (C-6) and B-1 (C-10), and oxalyl chloride in the presence of triethylamine in dichloromethane, followed by simple diethyl ether extraction of the reaction mixture, gave the corresponding aldehydes and ketones, respectively, in good yields with high purity. Similarly, the Corey Kim oxidation of various benzylic and allylic alcohols, primary alcohols, and secondary alcohols with two ion-supported methyl sulfides A-2 (C-6) and B-2 (C-10), and N-chlorosuccinimide in the presence of triethylamine in dichloromethane, followed by simple diethyl ether extraction of the reaction mixture, furnished the corresponding aldehydes and ketones, respectively, in good yields with high purity. Both reactions did not produce any unpleasant odor at all. In the Swern oxidation, ion-supported methyl sulfides were recovered in high yields and could be re-oxidized to produce ion-supported methyl sulfoxides A-1 (C-6) and B-1 (C-10), for reuse in the same oxidation. In the Corey Kim oxidation, ion-supported methyl sulfides A-2 (C-6) and B-2 (C-10) were recovered in high yields and could be also reused for the same oxidation. (C) 2012 Elsevier Ltd. All rights reserved.

Various aromatic bromides were treated with n-BuLi and subsequently with ethyl formate, followed by the reaction with ethanol and molecular iodine in the presence of K2CO3 to provide the corresponding aromatic ethyl esters in good yields. Moreover, aromatic bromides could be transformed into the corresponding aromatic methyl esters in good yields by the treatment with n-BuLi and subsequently with DMF, followed by the reaction with methanol, molecular iodine, and K2CO3. Some aromatics could be also converted into the corresponding aromatic esters in good yields by the treatment with n-BuLi, and subsequently with ethyl formate or DMF, followed by the reaction with molecular iodine and K2CO3. The present reactions offer a novel route for the transition-metal-free, carbon-monoxide-free, and therefore environmentally benign one-pot conversion of aromatic bromides and aromatics into aromatic esters. (C) 2012 Elsevier Ltd. All rights reserved.

Various electron-rich aromatics could be efficiently transformed into the corresponding aromatic nitrites in good to moderate yields by treatment with DMF and POCl3, followed by the reaction with molecular iodine or 1,3-diiodo-5,5-dimethylhydantoin (DIH) in aq NH3. Some of less reactive aromatics, such as anisole, 1,2-dimethoxybenzene, 1,4-dimethoxybenzene, and mesityrene, could be also transformed into the corresponding aromatic nitriles in good to moderate yields using N-methylformanilide and O(POCl2)(2), followed by the reaction with molecular iodine in aq NH3. Moreover, propiophenone derivatives could be successfully transformed into the corresponding beta-chlorocinnamonitriles by the reaction with DMF and POCl3, followed by the reaction with molecular iodine and aq NH3. These reactions are novel metal-free one-pot methods for the preparation of aromatic nitriles from electron-rich aromatics and beta-chlorocinnamonitriles from propiophenones. (C) 2012 Elsevier Ltd. All rights reserved.

The oxidation of secondary alcohols and primary alcohols with novel ion-supported (diacetoxyiodo)benzenes (IS-DIB) in the presence of a catalytic amount of 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO) in dichloromethane at room temperature proceeded efficiently to provide the corresponding ketones and aldehydes, respectively, in good yields with high purity. Isolation of the product was easily accomplished by simple diethyl ether extraction of the reaction mixture and subsequent removal of the solvent from the extract. Moreover, ion-supported iodobenzenes, which were co-products derived from IS-DIB in the present oxidation, were recovered in good yields and could be re-oxidized to IS-DIB for reuse in the same oxidation.

Various N,N-dimethyl aromatic amides were obtained in good to moderate yields by the reaction of aromatic aldehydes with aqueous dimethylamine in the presence of molecular iodine or 1,3-diiodo-5,5-dimethylhydantoin (DIH) at room temperature. Under the same conditions and using the same procedure, treatment of aromatic aldehydes and morpholine in the presence of DIH also provided the corresponding N-aroyl morpholines in good to moderate yields.

A direct benzylic oxidation of alkylarenes via C-H bond abstraction was developed using alkali metal bromides and oxidants under mild conditions. This reaction proceeded with excellent selectivity by thermal oxidation or photooxidation to provide a broad range of carbonyl compounds containing electron-deficient aryl carbonyl compounds in high yields.

Various N-tosyl arylimines reacted with methyl vinyl ketone and ethyl vinyl ketone in the presence of ion-supported Ph3P A and B to give adducts, N-(2'-methylene-3'-oxo-1'-arylbutyl)-4-methylbenzenesulfonamides and N-(2'-methylene-3'-oxo-1'-arylpentyl)-4-methylbenzenesulfonamides, respectively, in good yields with high purity by simple diethyl ether extraction of the reaction mixture. Moreover, ion-supported Ph3P A and B could be repeatedly used for the same reaction to provide the corresponding adducts while maintaining good yields with high purity. (C) 2012 Elsevier Ltd. All rights reserved.

The Hofmann-type rearrangement of aromatic and aliphatic imides using a hypervalent iodine(III) reagent generated in situ from Phl, m-CPBA, and TsOH center dot H2O proceeded in the presence of a base in alcohol to provide anthranilic acid derivatives and amino acid derivatives in high yields, respectively. This reaction proceeds through a tandem reaction via alcoholysis followed by a Hofmann rearrangement promoted by the formation of an imide-lambda(3)-iodane intermediate.

Aromatic ketones were efficiently prepared in good yields by the reactions of aryl bromides with n-BuLi, followed by the reactions with aromatic aldehydes or aliphatic aldehydes and the subsequent treatment with molecular iodine and K2CO3, in a one-pot method. The same treatment of arenes, instead of aromatic bromides, also provided the corresponding aromatic ketones in good yields. Using these methods, various diaryl ketones and alkyl aryl ketones bearing electron-rich aromatics and electron-deficient aromatics could be prepared efficiently by a simple, transition-metal-free, and therefore environmentally benign experimental procedure. (C) 2012 Elsevier Ltd. All rights reserved.

The Hofmann-type rearrangement of aromatic and aliphatic imides using KBr as the catalyst proceeded to provide aromatic and aliphatic amino acid derivatives. We have also developed a new synthetic route to gabapentin with this method.

The oxidation of primary and secondary alcohols with ion-supported methyl sulfoxide and oxalyl chloride in the presence of triethylamine in dichloromethane efficiently proceeded to give the corresponding aldehydes and ketones, respectively, in good yields with high purity. Isolation of the product was achieved very easily by simple diethyl ether extraction of the reaction mixture and subsequent removal of solvent from the extract. The reaction did not produce any unpleasant odor. Furthermore, ion-supported methyl sulfide was recovered in good yield and could be re-oxidized to ion-supported methyl sulfoxide for reuse in the same oxidation.

Various esters were efficiently converted into the corresponding nitriles in good yields by the treatment with sodium diisobutyl-tert-butoxyaluminium hydride (SDBBA-H), followed by treatment with molecular iodine in aq ammonia. The present one-pot method is very efficient and practical for the conversion of various aromatic and aliphatic esters into the corresponding nitrites. (C) 2011 Elsevier Ltd. All rights reserved.

The oxidative intramolecular bromo-amination of various N-alkenyl sulfonamides and N-alkenoxyl sulfonamides via umpolung of alkali metal bromides occurred exo-selectively to generate cyclic bromoamides in high yields with good diastereoselectivities. This method provided the desired products without elaborating the stoichiometric amount of corresponding organic waste.

Alkyl aryl ketones and dialkyl ketones could be converted into the corresponding alpha-tosyloxy ketones by the reaction with MCPBA and p-toluenesulfonic acid monohydrate (PTSA center dot H2O) in the presence of a catalytic amount of molecular iodine (I-2) in a mixture of acetonitrile and 2,2,2-trifluoroethanol, although the yields were dependent on the ketones (method A). The same conversion of alkyl aryl ketones and dialkyl ketones into the corresponding alpha-tosyloxy ketones could be smoothly carried out by the reaction with MCPBA and PTSA center dot H2O in the presence of catalytic amounts of iodine and tert-butylbenzene in a mixture of acetonitrile and 2,2,2-trifluoroethanol (method B). In those reactions, p-iodotoluene and 4-tert-butyl-1-iodobenzene were formed at first in method A and method B, respectively, and then they were converted into p-[(hydroxy)(tosyloxy)]iodotoluene and 4-tert-butyl-1-[(hydroxy)(tosyloxy)iodo]benzene by the reaction with MCPBA and PTSA center dot H2O. p[(Hydroxy)(tosyloxy)]iodotoluene and 4-tert-butyl-1-[(hydroxy)(tosyloxy)iodo]benzene worked as an alpha-tosyloxylation reagent of ketones.

Treatment of alkylbenzenes with (diacetoxyiodo)benzene in the presence of catalytic amounts of p-toluenesulfonamide or p-nitrobenzenesulfonamide, and molecular iodine in 1,2-dichloroethane at 60 degrees C gave the corresponding (cc-acetoxy)alkylbenzenes in good to moderate yields. The present reaction is a simple method for the introduction of an acetoxy group to the benzylic position of alkylbenzenes. (C) 2011 Elsevier Ltd. All rights reserved.

Various N,N-dimethyl amides, N-methoxy-N-methyl amides, and isopropyl esters were smoothly transformed into the corresponding nitriles in good to moderate yields by the treatment with diisobutylaluminium hydride, followed by treatment with molecular iodine in aq ammonia. The present reactions are novel one-pot and practical methods for the transformation of N,N-disubstituted amides and isopropyl esters into nitriles, through the formation of hemiaminal O-AlBu2 and hemiacetal O-AlBu2, respectively. (C) 2011 Elsevier Ltd. All rights reserved.

Various aromatic bromides were efficiently transformed into the corresponding aromatic nitriles in good yields via the formations of Grignard reagents and subsequently N,N-dimethyl formamide (DMF) adducts, followed by treatment with molecular iodine (I-2) in aq NH3 at room temperature. The present reaction is an easy and practical method for the preparation of aromatic nitriles from aromatic bromides with less toxic reagents, such as Mg, DMF, I-2, and aq NH3. (C) 2011 Elsevier Ltd. All rights reserved.

Ion-supported Ph3P, 4-(diphenylphosphino)benzyltrimethylammonium bromide A and N-methyl-N-[4(diphenylphosphino)benzyl]pyrrolidinium bromide B, were used for the Wittig reaction. Ion-supported phosphonium salts A1 and B1, which were prepared from the reactions of ion-supported Ph3P A and B with ethyl bromoacetate, respectively, reacted with aromatic and aliphatic aldehydes in the presence of K2CO3 to give the corresponding alpha,beta-unsaturated ethyl esters in good yields with high purity by simple filtration of the reaction mixture and subsequent removal of the solvent from the filtrate. Similarly, ion-supported phosphonium salts A2 and B2, which were prepared from the reactions of ion-supported Ph3P A and B with p-methylbenzyl bromide, respectively, reacted with aromatic and aliphatic aldehydes in the presence of NaH to provide the corresponding p-methylstyrene derivatives in good yields with high purity by simple filtration of the reaction mixture and the subsequent removal of the solvent from the filtrate. In both reactions, the co-product, ion-supported Ph3PO, could be obtained quantitatively by simple filtration, and was converted into the corresponding ion-supported Ph3P A and B again in high yields using dimethyl sulfate, followed by the reduction with LiAlH4. Recovered and regenerated ion-supported Ph3P A and B could be reused for the same Wittig reaction while maintaining good yields of ethyl (E)-3-(4'-chlorophenyl)-2-propenoate and 1 -(4'-chlorophenyl)-2-(4 ''-methylphenyl)ethene with high purity by simple filtration and removal of the solvent from the filtrate. (C) 2010 Elsevier Ltd. All rights reserved.

Various aromatic bromides and iodides were smoothly converted into the corresponding aromatic nitriles in good to moderate yields by the treatment with n-butyllithium and subsequently DMF, followed by treatment with molecular iodine in aq NH3. The same treatment of typical aromatics and hetero-aromatics with n-butyllithium and subsequently DMF, followed by treatment with molecular iodine in aq NH3 also provided the corresponding aromatic nitriles in good yields. Moreover, the same treatment of aromatic bromides and aromatics with half amount of DIH (1,3-diiodo-5,5-dimethylhydantoin) instead of molecular iodine worked effectively to give the corresponding aromatic nitriles, respectively, in good yields. These reactions are novel and environmentally benign one-pot methods for the preparation of aromatic nitriles from aromatic bromides and aromatics, respectively, through the formation of aryllithiums and their DMF adducts. (C) 2010 Elsevier Ltd. All rights reserved.

Various aromatic and aliphatic aldehydes were efficiently converted into the corresponding 1,4,5,6-tetrahydro-2-arylpyrimidines and 1,4,5,6-tetrahydro-2-alkylpyrimidines in good yields by the reaction with 1,3-propanediamine in the presence of molecular iodine center dot K2CO3 or 1,3-diiodo-5,5-dimethylhydantoin. Those 1,4,5,6-tetrahydropyrimidines were oxidized to the corresponding 2-aryl- and 2-alkylpyrimidines in moderate yields using MnO2.

Iodoarene-mediated cyclization of N-methoxy-2-arylethanesulfonamides with Oxone (R) was carried out to form the corresponding N-methoxy-3,4-dihydro-2,1-benzothiazine-2,2-dioxides in moderate to good yields in acetonitrile. In this reaction, reactive hypervalent iodine species, i.e., [(hydroxy)(tosyloxy)iodo]arenes, were formed in situ and reacted with N-methoxy-2-arylethanesulfonamides to form the corresponding N-methoxy-3,4-dihydro-2,1-benzothiazine-2,2-dioxides in an electrophilic manner on the aromatic ring. Ion-supported PhI could be also used for the same cyclization of N-methoxy-2-arylethanesulfonamides with Oxone to provide N-methoxy-3,4-dihydro-2,1-benzothiazine-2,2-dioxides in good to moderte yields. However, ion-supported PhI could not be reused for the same reaction. The same iodoarene-mediated cyclization of N-methoxy-3-phenylpropanamide and N-methoxy-4-phenylbutanamide with Oxone was also carried out to form the corresponding N-methoxybenzolactams in moderate yields.

Treatment of p-alkylbenzenesulfonic acids with mCPBA and molecular iodine gave p-alkyliodobenzenes in good to moderate yields via electrophilic ipso-substitution by the iodonium species (I*) formed. This desulfonyloxyiodination was promoted by the addition of a catalytic amount of iodoarenes, such as o-iodobenzoic acid. The same treatment of dimethylbenzenesulfonic acids and trimethylbenzenesulfonic acids with mCPBA and molecular iodine proceeded smoothly both in the absence and in the presence of o-iodobenzoic acid to provide the corresponding monoiodo-dimethylbenzene and diiodo-dimethylbenzene, and diiodo-trimethylbenzene and triiodo-trimethylbenzene, in good to moderate yields, respectively. On the other hand, the same desulfonyloxyiodination of benzenesulfonic acid and p-chlorobenzenesulfonic acid with mCPBA and molecular iodine proceeded only in the presence of o-iodobenzoic acid to generate iodobenzene and p-chloroiodobenzene, respectively, in moderate yields. (C) 2010 Elsevier Ltd. All rights reserved.

Various primary alcohols, particularly benzylic alcohols, could be converted into the corresponding aromatic amides in good yields in a one-pot manner by treatment with molecular iodine in aq. NH(3), followed by reaction with similar to 30% aq H(2)O(2) Similarly, various benzylic halides could be also converted into the corresponding aromatic amides in good yields in a one-pot manner by treatment with molecular iodine in aq NH(3). followed by reaction with similar to 30% act H(2)O. The present reactions Involve the metal-free one-pot oxidative conversion of benzylic alcohols and benzylic halides into the corresponding aromatic amides. respectively (c) 2010 Elsevier Ltd All rights reserved

Three novel polymer-supported iodobenzene compounds A(0), A(6), and A(10) were prepared from the reaction of commercially available cross-linked poly(p-chloromethyl) styrene with m-iodobenzylalcohol, 6-(m-iodobenzyloxy)-1-hexanol, and 10-(m-iodobenzyloxy)- 1-decanol. Their catalytic reactivity and reusability for the oxidative alpha-tosyloxylation of ketones and the cyclization of N-methoxy-2-arylethanesulfonamides in the presence of m-chloroperbenzoic acid (mCPBA) were confirmed to provide alpha-tosyloxy-ketones and N-methoxy-3,4-dihydro-2,1-benzothiazine-2,2-dioxides, respectively, in good yields.

Various aromatic bromides and iodides were smoothly converted into the corresponding aromatic nitriles in good to moderate yields by the treatment with butyllithium and subsequently DMF, followed by treatment with molecular iodine in aqueous ammonia. The same treatment of typical aromatics and heteroaromatics with butyllithium and subsequently DMF, followed by treatment with molecular iodine in aqueous ammonia also provided the corresponding aromatic nitriles in good yields. The present reactions are novel one-pot methods for the preparation of aromatic nitriles from aromatic bromides and aromatics, respectively, through the formation of aryllithiums and their DMF adducts.

Novel ion-supported Ph(3)P compounds, 4-(diphenylphosphino)-benzyltrimethylammonium bromide (A) and N-methyl-N-[4-(diphenylphosphino)-benzyl]pyrrolidinium bromide (B), were prepared. Because of their stability in air, ion-supported Ph(3)P A and B could be used for the halogenation of alcohols, the esterification of carboxylic acid with the Mitsunobu reaction, the Mizoroki-Heck reaction, and the Sonogashira reaction. The advantages of using these ion-supported Ph(3)P A and B are the simple isolation of the products by ether extraction due to their poor solubility in ether, and the easy recovery of the co-product, ion-supported Ph(3)PO, by filtration in high yields (>90%), which could be regenerated and reused for the same reactions, in the halogenation of alcohols and the esterification of carboxylic acid with the Mitsunobu reaction. On the other hand, ionic liquid reaction media containing Pd(OAc)(2) or PdCl(2) and ion-supported Ph(3)P A or B as catalysts could be reused for Me same Mizoroki-Heck reaction and the Sonogashira reaction maintaining high yields, using iodotoluene with methyl acrylate and phenylacetylene, respectively. (C) 2010 Elsevier Ltd. All rights reserved.

Various electron-rich aromatics could be smoothly converted into the corresponding aromatic nitriles in good to moderate yields by treatment of electron-rich aromatics with POCl(3) and DMF, followed by treatment with molecular iodine in aqueous ammonia. The present reaction is a novel metal-free one-pot method for the preparation of aromatic nitriles from electron-rich aromatics.

Treatment of alkylbenzenes with p-toluenesulfonamide and 1,3-diiodo-5,5-dimethylhydantoin (DIH) in a small amount of carbon tetrachloride at 60 degrees C gave the corresponding alpha-p-toluenesulfonylamido)alkylbenzenes in good to moderate yields. The present reaction is a simple method for the alpha-sulfonylamidation of the benzylic position in alkylbenzenes. (C) 2010 Elsevier Ltd. All rights reserved.