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The sulfonamide compound, 4-methyl-N-(naphthalene-1-yl)benzene sulfonamide (abbreviated as 4MNBS) was synthesized from the reaction of 4-methyl benzene sulfonyl chloride with 1-naphthyl amine. The 4MNBS was characterized by FTIR, 1H NMR, 1

Basicity constants, pKa, for a wide range of mono-protonated diaminobenzenes and diaminonaphthalenes, including dimethylamino derivatives were for the first time uniformly measured in 20% aqueous ethanol (29 compounds) and 80% aqueous dioxane (39 compounds) spanning from aniline to 1,8-bis(dimethylamino)naphthalene (‘proton sponge’). The dioxane system proved to be more versatile and because of better solubility of N-alkylated polyaminoarenes allowed to add to the same scale some superbasic bis(dialkylamino)-, tetrakis(dialkylamino)-, and hexakis(dialkylamino)naphthalenes, thus extending the scale for almost 10 pKa units, revealing possible limits of basicity changes in aromatic amines. The basicity of reference bases, pyridine and triethylamine, was also measured in these solvent systems. A group of N-alkylated compounds was found to be less basic in aqueous dioxane when compared with their NH2-analogs. This anomaly was not observed in aqueous ethanol. Other basicity trends and correlations between different basicity scales were also discussed. Copyright

The alteration of redox homeostasis is a hallmark of cancer cells. As a critical player in regulating cellular redox signaling, thioredoxin reductase (TrxR) enzymes are increasingly recognized as attractive targets for anticancer drug development. We repo

(Chemical Equation Presented) Electron-rich half-sandwich ruthenium complex CpRuI(PPh3)2, generated in situ, catalyzed the coupling reaction of 7-azabenzonorbornadienes with alkynes to form 3a,9b-dihydrobenzo[g] indoles. This transfo

Copper nitrene complexes are highly reactive species and are known as intermediates in the copper catalyzed C-H amination. In this study, three novel copper tosyl nitrene complexes were synthesized at low temperatures, stabilized with heteroscorpionate ligands of the bis(pyrazolyl)methane family. The copper nitrenes were obtained by the reaction of a copper(i) acetonitrile complex with SPhINTs in dichloromethane. We show that the ligand design has a major influence on the catalytic activity and the thermal stability of the copper nitrene complex. Not only the choice of the third N donor, but also the substituent in the 5-position of the pyrazolyl moiety, have an impact on the stability. Furthermore, the novel copper nitrene complexes were used for catalytic aziridination of styrenes and C-H amination reactions of aromatic and aliphatic substrates under mild reaction conditions. Even challenging substrates like benzene and cyclohexane were aminated with good yields. The copper nitrene complexes were characterized using UV/Vis spectroscopy, low temperature Evans NMR spectroscopy, density functional theory, domain-based local pair natural orbital coupled cluster calculations (DLPNO-CCSD(T)) and cryo-UHR mass spectrometry.

The development of Ni-catalyzed C?N cross-couplings of sulfonamides with (hetero)aryl chlorides is reported. These transformations, which were previously achievable only with Pd catalysis, are enabled by use of air-stable (L)NiCl(o-tol) pre-catalysts (L=P

A porous cross-linked poly (ethyleneamine)-polysulfonamide (PEA-PSA) as a novel organic support system is synthesized in the presence of silica template by nanocasting technique. The paper demonstrates immobilization of CuI nanoparticles inside the pores (PEA-PSA?CuI) for the facile recovery and recycling of these nanoparticles. The presence of porous PEA-PSA and PEA-PSA?CuI nanocomposites was confirmed using FT-IR spectroscopy, FE-SEM, EDX, TGA, XRD, TEM, BET, XPS, WDX, 1H NMR, and ICP-OES techniques. The PEA-PSA?CuI along with Ag(I)/K2S2O8 was implemented as a reusable cooperative catalyst-oxidant system in the N-arylation of p-toluenesulfonamide with substituted carboxylic acids in mild condition. So, the novel decarboxylative cross-coupling catalyzed by copper and silver has been developed. Aromatic, secondary and tertiary aliphatic acids underwent high efficient decarboxylative processes with p-toluenesulfonamide to afford the corresponding products. This method provides a practical approach for the flexible synthesis of sulfonamides from the readily affordable substrates. The catalyst is highly reusable and efficient, especially in terms of time and yield of the desired product.

A simple copper-catalyzed redox coupling of sodium sulfinates and nitroarenes is described. In this process, abundant and stable nitroarenes serve as both the nitrogen sources and oxidants, and sodium sulfinates act as both reactants and reductants. A variety of aromatic sulfonamides were obtained in moderate to good yields with broad substrate scope. No external additive is employed for this kind of transformation.

An alternative approach with eco-friendliness and high efficiency for the preparation of unsymmetrical diaryl sulfones has been developed. The strategy takes advantage of the reaction of sulfonyl hydrazides with quinone imine ketals catalyzed by DABCO (triethylenediamine) in ethanol. This transformation proceeds via a Lewis base promoted, direct 1,4-conjugate addition/sulfonylation/alcohol elimination reaction sequence. The protocol provides an efficient approach to access an array of diverse unsymmetrical diaryl and heterodiaryl sulfones, aryl alkyl sulfones and aryl vinyl sulfones in good to excellent yields.

Cycling between Au(i) and Au(iii) is challenging, so gold-catalyzed cross-couplings are rare. The (MeDalphos)AuCl complex, which we showed was prone to undergo oxidative addition, is reported here to efficiently catalyze the C-N coupling of aryl iodides and amines. The transformation does not require an external oxidant or a directing group. It is robust and works with a wide scope of aryl iodides and N-nucleophiles under mild conditions. Mechanistic studies, including the NMR and MS characterization of a key aryl amido Au(iii) complex, strongly support a 2e redox cycle in which oxidative addition precedes transmetalation and reductive elimination is the rate-determining step.

A newly developed chemoselective reaction of sodium arylsulfinates or arylsulfonyl chlorides with nitroarenes has been disclosed. The chemistry, in which non-toxic water and recyclable iron-based metal-organic frameworks are employed as the solvent and catalyst, respectively, provides an efficient approach for the generation of N-arylsulfonamides, which are widely present in biologically active compounds and drugs, rendering this methodology attractive to both synthetic and medicinal chemistry.

An efficient three-component domino reaction among oxa(aza)bicyclic alkenes, sodium azide, and primary haloalkanes is reported, which offers a mild access to 1,2,3-triazolines in an aqueous medium with excellent diastereoselectivities and yields. Further studies show that, water-promoted isomerization of oxa(aza)bicyclic alkenes can afford 1-naphthol derivatives in good yields. Water not only promotes the reaction, but also provides a recyclable and sustainable approach to the desired product. In addition, a novel metal-free cascade ring-opening/rearrangement reaction of the obtained bicyclic triazolines to form multifunctionalized indenes has been discovered.

In this report, we have explored a triple mode of chemical reactivity of ethyl bromodifluoroacetate. Typically, bromodifluoroacetic acid has been used as a difluorocarbene precursor for difluoromethylation of soft nucleophiles. Here we have disclosed nucleophilicity and base dependent divergent chemical reactivity of ethyl bromodifluoroacetate. It furnishes lithium hydroxide and cesium carbonate promoted difluoromethylation of tosyl-protected aniline and electron-deficient phenols respectively. Interestingly, switching the base from lithium hydroxide to 4-N,N-dimethylamino pyridine (DMAP) tosyl-protected anilines afforded the corresponding N-ethylation product. Whereas, highly nucleophilic thiophenols furnished the corresponding S-carboethoxydifluoromethylation product via a rapid SN2 attack to the bromine atom prior to the ester hydrolysis. This mechanistic divergence was established through several control experiments. It was revealed that difluoromethylation reaction proceeds through a tandem in situ ester hydrolysis/decarboxylative-debrominative difluorocarbene formation and subsequent trapping by the soft nucleophile-NHTs or electron-deficient phenolic ?OH groups. In the presence of DMAP the hydrolysis of the ester is perturbed instead a nucleophilic attack at the ethyl moiety provides the N-ethylation product. Hence, besides the development of a practical base-promoted N-difluoromethylation of amines and electron-deficient phenols, divergent reactivity pattern of inexpensive and user-friendly ethyl bromodifluoroacetate has been explored. (Figure presented.).

A copper-catalyzed Chan-Lam-coupling-like reaction of a (het)arylboronic acid and chloramine-T (or a related compound) has been developed for the synthesis of N -arylsulfonamides at room temperature in moderate to good yields, with good tolerance of functional groups. In this process, it is believed that chloramine-T serves as an electrophile.

A heterogeneous Chan-Lam coupling reaction between sulfonyl azides and arylboronic acids was achieved in MeOH at room temperature in the presence of 10 mol% of an l-proline-functionalized MCM-41-immobilized copper(i) complex [MCM-41-l-proline-CuCl] under air, yielding a variety of N-arylsulfonamides in excellent yields. The new heterogeneous copper complex can be prepared from commercially readily available and inexpensive reagents, and recovered by simple filtration of the reaction solution and recycled at least 8 times without any decreases in activity.

A palladium-catalyzed construction for N-arylsulfonamide from nitroarenes and arylsulfonyl hydrazides is developed. In this protocol, abundant and stable nitroarenes serve as the nitrogen sources by in situ reduction reaction of hydrogen released from arylsulfonyl hydrazides. No external oxidants or reductants are needed for this kind of transformation.

One-step, catalytic synthesis of N-arylsulfonamides via the construction of N-S bonds from the direct coupling of sodium arylsulfinates with nitroarenes was realized in the presence of FeCl2 and NaHSO3 under mild conditions. In this process, stable and readily available nitroarenes were used as nitrogen sources, and NaHSO3 acted as a reductant to provide N-arylsulfonamides in good to excellent yields. A broad range of functional groups were very well-tolerated in this reaction system. In addition, mechanistic studies indicated that the N-S bond might be generated through direct coupling of nitroarene with sodium arylsulfinate prior to the reduction of nitroarenes by NaHSO3. Accordingly, a reaction mechanism involving N-aryl-N-arenesulfonylhydroxylamine as an intermediate was proposed.

A palladium-catalyzed domino N-benzylation/intramolecular direct arylation involving sulfonanilides and 2-bromobenzyl bromides has been developed for the first time, providing a workable access to N-sulfonyl dihydrophenanthridines in good to excellent yields. Under the optimized conditions, the formation of 5,6-dihydrophenanthridines was largely controlled over the formation of biaryl sultams containing a seven member ring. The optimized condition was found extendable to the regiocontrolled domino formation of N-sulfonyl-6,7-dihydro-5H-dibenzo[c,e]azepines over the biaryl sultam formation. Using an appropriate substrate, a biaryl sultam has been obtained exclusively.

A novel asymmetric ring-opening reaction of N-substituted azabenzonorbornadienes with a wide variety of substituted benzyl alcohols and the addition reaction of N-substituted azabenzonorbornadienes with thiols are reported, affording the corresponding 1,2-trans-alkoxyamino products in moderate yields with excellent enantioselectivities (up to 94% ee) and the corresponding thiol addition products in high yields with lower enantiomeric excesses (ee) in the presence of iridium catalyst, respectively. The effects of ligands, catalyst loading, solvents and additives, and temperature were also investigated. The anti-configuration of the product 3c was confirmed by X-ray crystal structure analysis. A possible mechanism for the present catalytic reaction is proposed.

A small focused chemical library constituted of sulfonamides was synthesized. These compounds were designed to lack the p-aminobenzene moiety typically found in sulfonamide antibiotics. Antimicrobial activities of these synthetic compounds were investigated against global predominant methicillin-resistant Staphylococcus aureus (MRSA) strain USA300 (SF8300) and control strains of Staphylococcus aureus (S. aureus) ATCC 25923 and ATCC 29213 using disk diffusion and microdilution assays. Based on susceptibility results, potent S. aureus and MRSA USA300 growth inhibitors such as N-[3,5- bis(trifluoromethyl)phenyl]-4-bromobenzenesulfonamide with minimum inhibitory concentration (MIC) as low as 5.6 μg/cm3 along with other effective sulfonamides were discovered. Structure-activity correlations revealed that these desamino-benzenesulfonamides required electron-withdrawing substituents to be effective inhibitors of bacterial pathogen growth. In addition, their ability to inhibit growth of S. aureus strains was retained even when bacterial folate synthetic intermediate, p-aminobenzoic acid (PABA), was supplemented, whereas PABA supplementation completely diminished the antibacterial activity of the known sulfa drug tested, sulfamethoxazole. The sulfa-resistant MRSA strain COL also showed great susceptibility to these desamino-benzenesulfonamides. These results imply a unique mechanism of growth inhibition by these potent desamino-benzenesulfonamides, different from the well-known folate pathway target of sulfonamide antibiotics.

A methodology involving a "transition metal-free" intramolecular biaryl-coupling of o-halo-N-arylbenzylamines has been developed in the presence of potassium tert-butoxide and an organic molecule as catalyst. The reaction appears to proceed through KOtBu-promoted intramolecular homolytic aromatic substitution (HAS). Interestingly, this biaryl coupling also works in the presence of potassium tert-butoxide as sole promoter. On extending our approach further, we found that N-acyl 2-bromo-N-arylbenzylamines undergo a one-pot N-deprotection/biaryl coupling followed by oxidation, thus offering an expeditious route to the phenanthridine and benzo[c]phenanthridine skeletons. The strategy has been applied to a concise synthesis of Amaryllidaceae alkaloids viz. oxoassoanine (1b), anhydrolycorinone (1d), 5,6-dihydrobicolorine (2d), trispheridine (2b), and benzo[c]phenanthridines alkaloids dihydronitidine (3b), dihydrochelerythidine (3d), dihydroavicine (3f), nornitidine (3h), and norchelerythrine (3j).

An efficient protocol for direct arylsulfonamidation of aryl iodides and aryl bromides using arylsulfonylazides catalyzed by copper nanoparticles is described. Iranian Chemical Society 2012.

Dehydrogenative aromatization of cyclohexanone imines to arylamines has been achieved using a palladium catalyst under aerobic conditions. The reaction is applicable to a variety of imines that are either preformed or generated in situ from cyclohexanone derivatives and aryl or alkylamines.

The asymmetric ring-opening of azabicyclic alkenes with a variety of phenols is investigated using an iridium catalyst generated in situ from 2.5 mol % of [Ir(COD)Cl]2 and 5.0 mol % of (S)-BINAP, which afforded the corresponding 1,2-trans-phenoxyamino products in excellent yield (up to 92%) with moderate to good enantioselectivities (up to 98% ee). The trans-configuration of the product 4b was confirmed by X-ray crystallography.

Rhodium(III)-catalyzed oxidative olefination of N-(1-naphthyl)sulfonamides has been achieved at the peri position. Three categories of olefins have been successfully applied. Activated olefins reacted to afford five-membered azacycles as a result of oxida

A simple and efficient method has been developed for the sulfonylation of several amines, alcohols, and phenols by p-toluenesulphonylchloride (p-TsCl) in the presence of catalytic amount of Cs2CO3 at 25C to obtain sulfonamides and sulfonic esters in very good yields. Cs2CO3 has been found to be highly efficient catalyst. Taylor & Francis Group, LLC.

The preparation of N-acylsulfonamides is described using primary amines, arylsulfonyl chlorides and acyl chlorides. Reaction of primary aryl amines with arylsulfonyl chlorides in the presence of NaHCO3 produced N-arylsulfonamides, which reacted in situ with benzoyl chloride furnishing the corresponding N-benzoyl-N-arylsulfonamides in 72-96% yields. Accordingly, 4-nitrobenzoyl chloride and 3,5-dinitrobenzoyl chloride were used as acylating agents. All the reactions were carried out under solvent-free conditions at room temperature and the products were isolated after simple work-up in high yields and purity.

(Chemical Equation Presented) Cationic rhodium(I)-catalyzed cyclodimerization of oxabenzonorbornadienes produced naphtho[1,2-b]-furan ring systems in a single step with excellent yields and excellent enantioselectivities. The effect of various Rh(I) catalysts, Ag(I) salts, solvents, and phosphine ligands on the yield and enantioselectivity of the reaction was investigated, and the scope and limitations of this reaction with various oxabicyclic alkenes were studied. Similar results were obtained with the azabenzonorbornadiene analogues, providing the corresponding cyclodimerization products in excellent yields and excellent enantioselectivities.

In this paper, a series of N-aryl substituted toluenesulfamides were synthesised by grinding under solvent-free conditions at room temperature. The yields were excellent (88%-97%), and the process is simple.

1-Naphthols efficiently couple with internal alkynes via cleavage of the C-H bond at the peri-position in the presence of a catalyst system of [IrCl(cod)]2/PBut′3 to selectively afford the corresponding 8-vinyl-1-naphthol derivatives. N-(1-Naphthyl)benzenesulfonamides can similarly react with the alkynes. The reaction of salicylaldehyde with the alkynes using the catalyst system gives 2-hydroxyphenyl vinyl ketones via cleavage of the aldehyde C-H bond.

When transfering the title reaction to the 2- and 1-naphthyltoluenesulfonamides 5 and 10, the -shift of the arylsulfonyl group proceeds into the 3- and 2-position (to give 9 and 12, respectively), which is in full compliance with optimal conjugative and steric conditions for the relevant intermediates 8 and 11.Attemps to initiate comparable -rearrangements through the o-lithiated biphenyl derivative 17 and the p-lithiated N-phenyltoluenesulfonamide 23 led again, after extended transmetalation cascades, to the conventional -rearrangement products 22 and 32, respectively.In attempting to cause in the o-tolylbenzenesulfonamide 49 an anionically induced -sulfonyl shift into the benzyl position, two fragments of the starting molecule combined to give the novel heteropolycycle 51.Finally, it could be shown that contrary to the literature, the sulfonamides 46 and 57 rearrange also photolytically to the o-aminosulfones 45 and 58.