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This account aims to give a description of the usefulness of diaryliodonium salts in organic chemistry, including their synthesis and applications in the presence and absence of transition-metal catalysts. Herein, we briefly summarize the structural properties and reactivity of diaryliodonium salts. We describe several applications of these hypervalent reagents including metal-free arylations of C-, O-, N- and S-nucleophiles. The synthesis and functionalization of aromatic and heteroaromatic systems via copper- and palladium-catalyzed transformations are also discussed in this account. 1 Introduction 2 Structural Properties and Reactivity 3 Applications of Diaryliodonium Salts in Organic Syntheses 3.1 Transition-Metal-Free Arylations of Heteroatom and Carbon Nu- cleophiles 3.1.1 Arylation of Oxygen Nucleophiles 3.1.1.1 Arylation of (Hetero)aromatic Alcohols 3.1.1.2 Arylation of Aliphatic Alcohols 3.1.1.3 Arylation of Acids 3.1.2 Arylation of Nitrogen Nucleophiles 3.1.2.1 N-Arylation of Amines and Amides 3.1.2.2 N-Arylation of Heterocycles 3.1.3 Arylation of Sulfur Nucleophiles 3.1.4 Arylation of Inorganic Anions 3.1.5 Arylation of Carbon Nucleophiles 3.1.5.1 Electron-Rich Heterocycles 3.1.5.2 Arylation of Carbonyl and Nitro Compounds 3.2 Synthesis and Functionalization of Aromatic and Heteroaromatic Molecules with Diaryliodonium Salts in the Presence of Copper and Palladium Catalysts 3.2.1 C-H Functionalizations by Copper-Catalyzed C-H Arylations 3.2.2 Copper-Catalyzed Cyclization of Unsaturated Compounds with Diaryliodonium Salts 3.2.3 Palladium-Catalyzed Arylations 3.2.3.1 Electrophilic Palladation and Arylation 3.2.3.2 Directing-Group-Assisted C-H Bond Activation and Arylation 4 Conclusion [ABSTRACT FROM AUTHOR]

Cu3(BTC)2 is an efficient and reusable heterogeneous catalyst for the dehydrogenative coupling of silanes with alcohols. Activity data and CO adsorption suggest that Cu(ii) and in situ generated Cu(i) are the active species. Other MOFs such as Fe(BTC), MIL-101(Cr) and UiO-66(Zr) are unable to promote this cross-coupling. [ABSTRACT FROM AUTHOR]

A multi-stimuli responsive small molecule organic material has been developed, which for the first time exhibits dual-wavelength response to render photocoloration under visible light and turn-on luminescence under UV light. The colored product can be bleached and shows turn-on luminescence again when re-exposed to UV light. [ABSTRACT FROM AUTHOR]

Cu3(BTC)2 is an efficient and reusable heterogeneous catalyst for the dehydrogenative coupling of silanes with alcohols. Activity data and CO adsorption suggest that Cu(ii) and in situ generated Cu(i) are the active species. Other MOFs such as Fe(BTC), MIL-101(Cr) and UiO-66(Zr) are unable to promote this cross-coupling. [ABSTRACT FROM AUTHOR]

An interview with Matthew J. Fuchter, a reader in chemistry at Imperial College London in England, is presented. Topics discussed include the focus of his existing research activity is to use expertise in chemical synthesis to impact molecular science in biology, materials, and chemistry, his opinion about the modern role and prospects of organic synthesis, and his most importance scientific achievement.

One-pot synthesis in organic chemistry is deeply rooted in people's minds due to its huge improvement in efficiency compared with conventional stepwise synthesis. Nowadays, such a concept has also been shifted to polymer chemistry by one-pot introducing compatible or orthogonal organic reactions with polymerizations for facilely synthesizing or modifying polymers. This review systematically summarizes recent developments in the one-pot combination of enzymatic reactions with controlled radical polymerization to prepare functional polymers. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Using air as the oxygen source, 4-carbonyl-2-perfluoroalkylquinolines were prepared in good to excellent yields, from readily available 2-alkynylanilines and methyl perfluoroalk-2-ynoates through a CuII-promoted sequential process that omits the isolation of the enamine intermediates. The reaction tolerates several useful functionalities including ether, ester and chloro substituents. [ABSTRACT FROM AUTHOR]

A series of poly(methacrylic acid)- l-polyisobutylene anionic amphiphilic conetworks with hydrophobic polyisobutylene (PIB) content between 33% and 70% (w/w) is synthesized by the macromonomer method using a new approach by applying ethoxyethyl-protected methacrylic acid (EEMA) comonomer. To remove the protecting group after copolymerization of EEMA with PIB-dimethacrylate, acidic hydrolysis and thermal treatment are attempted, and the success of the deprotection is monitored by different techniques. Comparing the two protective group removal steps, it is found that, in contrast to homopolymers of EEMA, the acidic hydrolysis is more favorable than the thermal deprotection due to anhydride formation during the latter process in the conetworks. Distinct glass transitions are obtained by differential scanning calorimetry (DSC) indicating phase separation in the resulting conetworks. The swelling ability of the obtained conetworks in polar and nonpolar solvents proves the amphiphilic nature of these materials. Due to the polyacidic component of the conetworks, their water swollen gels have pH-sensitive, intelligent swelling behavior in aqueous media. Because of the relatively high stability of EEMA, the applied protection-deprotection strategy can be easily utilized in several other designed polymer syntheses. [ABSTRACT FROM AUTHOR]

The diastereoselective synthesis of (+)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline-1-carboxylic acid (90 % ee) was accomplished by employing a combination of two synthetic methods, that is, the Petasis synthesis of amino acids and the Pomeranz-Fritsch-Bobbitt synthesis of tetrahydroisoquinoline derivatives. The stereochemical outcome of the synthesis was controlled by chiral aminoacetaldehyde acetals, which were used as the amine component of the Petasis step to yield the Pomeranz-Fritsch-Bobbitt substrate for the tetrahydroisoquinoline ring formation in one simple operation. [ABSTRACT FROM AUTHOR]

A new and efficient protocol is described for the one-pot synthesis of benzimidazoles from a variety of aryl alcohols and 1,2-diaminoarenes. The yields were ranging from moderate to excellent. Moreover, the present method is utilizing alcohols instead of aldehydes and the reactions are carried out under solvent- and catalyst-free conditions, offering an environmentally benign process. [ABSTRACT FROM AUTHOR]

The introduction of side chains at the 1- and 9-positions of dipyrromethanes was explored by using the hetero-Diels-Alder reaction of azoalkenes. New 5,5′-diethyldipyrromethanes and 5-phenyldipyrromethanes that were functionalized with open-chain hydrazone moieties, including derivatives with tetrazolyl groups, were prepared. Furthermore, the synthesis of new calix[4]pyrroles and bilanes was achieved by employing the bis(hetero-Diels-Alder) reaction of azoalkenes with 5,5′-diethyldipyrromethane. [ABSTRACT FROM AUTHOR]

A TiIII-mediated radical cyclization cascade has been used for the synthesis of the sesquiterpenes (+)-albicanol, (+)-drimanol, and (+)-drimanic acid. Starting from all- trans-farnesol, (+)-albicanol could be prepared in seven steps in an overall yield of 14.9 %. Furthermore, a highly diastereoselective hydrogenation of (+)-albicanol to give (+)-drimanol has been developed. We used the synthesized (+)-drimanic acid to achieve the first synthesis of the marine sesquiterpene hydroquinone deoxyspongiaquinol and the quinone deoxyspongiaquinone. Thus, this synthetic strategy gave access to five natural products. [ABSTRACT FROM AUTHOR]

The reaction mechanisms and chemoselectivity on the intramolecular allylic C-H amination versus alkene aziridination of 4-pentenylsulfamate promoted by four elaborately selected dirhodium paddlewheel complexes are investigated by a DFT approach. A predominant singlet concerted, highly asynchronous pathway and an alternative triplet stepwise pathway are obtained in either C-H amination or alkene aziridination reactions when mediated by weak electron-donating catalysts. A singlet stepwise C-H amination pathway is obtained under strongly donating catalysts. The rate-determining step in the C-H amination is the H-abstraction process. The subsequent diradical-rebound C-N formation in the triplet pathway or the combination of the allylic carbocation and the negative changed N center in the singlet pathway require an identical energy barrier. A mixed singlet-triplet pathway is preferred in either the C-H insertion or alkene aziridination in the Rh2(NCH3CHO)4 entry that the triplet pathway is initially favorable in the rate-determining steps, and the resultant triplet intermediates would convert to a singlet reaction coordinate. The nature of C-H amination or alkene aziridination is estimated to be a stepwise process. The theoretical observations presented in the paper are consistent with the experimental results and, more importantly, provide a thorough understanding of the nature of the reaction mechanisms and the minimum-energy crossing points. [ABSTRACT FROM AUTHOR]

A new pyridine-acylamide ligand, L-L-N¹,N4-di(pyridin-3-yl)naphthalene-1,4-dicarboxamide, has been synthesized. Based on L, four types of carboxylate ligands as co-ligands and two metal ions (Zn(II) and Cd(II)), seven new metal-organic frameworks have been synthesized and structurally characterized. Compounds 1 and 2 are composed of SBU I (a helical {Zn(L)}n chain), while compounds 3-7 are composed of SBU II (a M2L2 metallocycle). In 1, with Hbtc²- anions connected to the neighboring Zn(II) ions of one SBU I, an infinite 1D chain is formed, while in 2, the neighboring SBUs I are bridged by ip²- anions forming a 2D structure. With SBUs II extended by oba²- ligands, compound 3 shows a 2D network. Compound 4 exhibits a 1D infinite chain with SBUs II bridged by nap²- ligands. Compounds 5 and 6 are isomers in which SBUs II are extended by nap²- ligands to afford a 2D network. In compound 7, SBUs II are linked together by Hbtc²- ligands featuring an infinite 1D chain. All of these compounds have a 3D framework governed by hydrogen bond interactions. Comparing all the compounds, it can be seen that the structural characteristics of the L ligand and organic counteranions simultaneously play an important role in their construction. Moreover, their thermostability and photoluminescence properties were explored. [ABSTRACT FROM AUTHOR]

The success of the application of transition-metal catalysts in asymmetric synthesis was recognized in the form of the 2001 Nobel Prize in Chemistry, but since then the field of asymmetric organic synthesis has been dominated by organocatalysts, due to their ability to catalyze a variety of fundamentally important transformations. One example is the Staudinger synthesis of β-lactams, which continue to provide unique opportunities for the design and synthesis of new derivatives with unprecedented biological profiles. During the last two decades, medicinal chemists have convincingly demonstrated that structural modification of monocyclic β-lactams (monobactams) is an effective procedure for the discovery of new pharmacological properties other than antibacterial activity. This microreview covers the progress in asymmetric organocatalytic synthesis of β-lactams since 2001, including the initial work on processes based on chirally modified transition-metal catalysts, because these have led the way to the more significant advances presented here. [ABSTRACT FROM AUTHOR]

We have developed a method for the synthesis of dimethyl 7-aryl-8-(3-arylquinoxalin-2-yl)-2-(R-imino)-9-oxo-1,6-dioxaspiro[4.4]nona-3,7-diene-3,4-dicarboxylates, based on a three-component reaction of 5-aryl-4-(quinoxalin-2-yl)furan-2,3-diones, 1-adamantylisocyanide or о-methylphenylisocyanide, and dimethyl acetylenedicarboxylate. [ABSTRACT FROM AUTHOR]

The BF3·Et2O-catalyzed formal [3 + 2] reaction of aziridinofullerenes with various carbonyl compounds for the easy preparation of fullerooxazolidines has been developed. Moreover, the reaction of aziridinofullerene with ethyl formate affords the simplest fullerooxazole without substituent. [ABSTRACT FROM AUTHOR]

An efficient and concise protocol for the highly regio- and stereoselective synthesis of ferrocene-containing disubstituted E-allylic ester derivatives via a palladium-catalyzed intermolecular arylesterification reaction of ferrocenylallene with aryl iodides and carboxylic acids has been developed. The regio- and stereoselectivities of this reaction may be controlled by the steric effect of the bulky ferrocene group. [ABSTRACT FROM AUTHOR]

A direct and scalable route to γ-keto-α,β-unsaturated esters, useful intermediates in medicinal chemistry and natural products synthesis, is reported. The key step involves the use of Grubbs' second-generation olefin metathesis catalyst for cross-metathesis of alkyl acrylates and 2° allylic alcohols. The metathesis step is followed by oxidation to give the desired products in high yield on scales of up to 25 g. [ABSTRACT FROM AUTHOR]

A general method for the synthesis of amides involving the direct coupling of alkali metal carboxylate salts with amines is described. Amidation of a wide variety of carboxylate salts with either free amines or their ammonium hydrochloride salts can be achieved using HBTU as a coupling agent in combination with Hünig's base. The reaction is highly efficient and is generally complete in as little as 1-2 h, giving the products in good to excellent yields. The protocol is valuable for the coupling of carboxylates for which the corresponding carboxylic acids or acyl chlorides are unstable, less conveniently manipulated/isolated, or are not commercially available. For example, the coupling of amines and α-amino acids with lithium 5-bromo-1H-pyrrole-2-carboxylate, whose corresponding acid that is prone to decarboxylation, allowed for the synthesis of 5-bromo-1H-pyrrole-2-carboxamides, which are analogues of the pyrrole-2-aminoimidazole marine alkaloids. The protocol can be combined with other reactions in a sequenced fashion, as exemplified by the synthesis of acetylenic amides, in a one-pot procedure, via the coupling of a lithium carboxylate salt formed initially by the addition of carbon dioxide to a lithiated terminal alkyne. [ABSTRACT FROM AUTHOR]

The chemistry of 2- C-formyl-glycals has witnessed tremendous growth over the last two decades. Functionalized compounds derived from 2- C-formyl-glycals have found applications in organic synthesis, carbohydrate chemistry, medicinal chemistry, supramolecular chemistry, and materials chemistry. These advancements can be mainly attributed to the availability of a very simple and general procedure for the direct formylation of glycals by using the Vilsmeier-Haack reaction. The highly conjugated α,β-unsaturated carbonyl functional group present in 2- C-formyl-glycals provides opportunities for synthetic elaboration, which can lead to a variety of natural and unnatural compounds for varied applications. This review summarizes the recent developments in the synthesis and applications of these versatile chiral intermediates. [ABSTRACT FROM AUTHOR]

The Kulinkovich cyclopropanation of esters with disubstituted homoallylic alcohols is described for the preparation of 1,2,3-trisubstituted cyclopropanols. Central to the successful implementation is the generation in situ of a temporary alkoxy tether between a homoallylic alcohol and an alkoxytitanium species to override unfavorable steric factors. [ABSTRACT FROM AUTHOR]

The synthesis of (±)-7-deoxythysanone and three analogues has been developed. The key oxa-Pictet-Spengler reaction enabled the synthesis of the naphthopyran precursor, which could be readily converted to 7-deoxythysanone and three related analogues. The biological activity of these compounds was also evaluated against HRV 3C protease, the results of which suggest that inhibition of the enzyme requires the presence of the 7-oxa functionality. [ABSTRACT FROM AUTHOR]

Short oligodeoxyribonucleotides have been assembled from appropriately protected nucleoside 3′-(benzotriazol-1-yl 2-chlorophenyl phosphate) derivatives on hundred-milligram scales on a soluble tetrakis- O-(4-azidomethylphenyl)pentaerythritol support bearing four 3′- O-(4-pentynoyl)thymidines. Small-molecule reagents and waste were removed by two precipitations of the support-bound growing oligonucleotides with methanol, the first after removal of the 5′-protecting group and the second after coupling. The building blocks were obtained by one-step phosphorylation of commercially available protected nucleosides with bis(benzotriazol-1-yl) 2-chlorophenyl phosphate. Removal of the phosphate protecting groups from the completed chain with ( E)-2-nitrobenzaldoxime followed by conventional ammonolysis allowed precipitation of the oligonucleotide as the sodium salt with ethanol. [ABSTRACT FROM AUTHOR]

Rapidly aSSembled: The combination of cobalt‐catalyzed migratory arylzincation and copper‐mediated/catalyzed chalcogenative cyclization allows the construction of benzothiophenes and benzoselenophenes from arylzinc reagents, alkynes, and elemental chalcogens. Benzothiophenes and benzoselenophenes diversely functionalized at the benzene ring moiety can be prepared, which are not readily accessible by conventional methods. [ABSTRACT FROM AUTHOR]

An iron-catalyzed reaction of 2-arylpyridine C-H bond with 2-bromoacetophenone is achieved, providing pyrido[2,1-a]- isoindoles in moderate to good yields. The regioselectivity stems from the domination of hindrance on the regioselective ortho-func- tionalization of 2-arylpyridines C-H bond. [ABSTRACT FROM AUTHOR]

Boronic acid derivatives have become important intermediates in organic and medicinal chemistry and, as a result, the development of new methods that permit the efficient creation of C-B bonds under mild conditions has become an active field of research in organic synthesis. In the last ten years, copper-catalyzed borylation reactions have emerged as versatile new tools for introducing boron atoms into organic molecules. Here, we describe our recent research in this field. We have developed two copper-catalyzed borylation reactions. The first involves the SN2' addition of bis(pinacolato)diboron to allylic epoxides. This reaction permits the stereoselective synthesis of a wide range of compounds containing a 1,4-diol moiety, a fragment that is present in many natural products with important biological activities. The second reaction is a copper-catalyzed formal carboboration process. In this reaction, a C-B and a C-C bond are created in a single catalytic cycle, and the method provides a new tool for the synthesis of tri- and tetra-substituted vinylboronates. [ABSTRACT FROM AUTHOR]

The AgNO3-mediated in situ scission of aromatic disulfides in the presence of electron-rich aromatic compounds results in the efficient synthesis of diaryl sulfides. Key features of this new methodology are high yields of aromatic and heteroaromatic sulfides, mild reaction conditions, simplicity, simple workup, and avoiding foul-smelling reactants like thiols. [ABSTRACT FROM AUTHOR]

Phosphonated benzoxazole derivatives are good candidates as ligands for metal complexes. Two regioisomers were synthesized with the phosphonate function at the C-4 and C-7 positions. Different alkyl chains were also introduced at the C-2 position to functionalize these two regioisomers and increase their complexation properties. The formation of coordination complexes of selected benzoxazoles with M2+ and M3+ metal cations has been screened in solution using HRMS (high-resolution mass spectrometry) as the analytical tool. [ABSTRACT FROM AUTHOR]

Chiral pyrrolidine-based organocatalysts, in combination with ionic-liquid-supported Brønsted acids, catalyze the enantioselective Michael addition of ketones and aldehyde to nitroolefins in high yields with high enantioselectivities (ee ≤ 96%) and diastereoselectivities (syn/anti ratio ≤ 98:2). This novel process provides synthetically useful γ-nitrocarbonyl compounds, which can be easily transformed into other invaluable precursors of biologically active compounds. In addition, the synthetic procedure presented is simple and practical. [ABSTRACT FROM AUTHOR]

Synthetic studies on a 17ß-hydroxysteroid dehydrogenase type 3 (17ß-HSD3) inhibitor are described. The unsymmetrical dibenzazocine skeleton was constructed by a regiocontrolled ring-expansion reaction of a cyclic oxime with DIBAL-H. [ABSTRACT FROM AUTHOR]

The copper(I) chloride catalyzed reaction of azides with alkynes in water at room temperature was promoted by the addition of a catalytic amount of 2-ethynylpyridine, affording the corresponding 1,4-disubstituted 1,2,3-triazoles in good yields after a specific reaction time. The catalytic system could be successfully applied to electron-rich, electron-poor, and sterically crowded substrates. A study of the additive effect of pyridine derivatives revealed that alkynyl and 2-pyridyl groups were essential for activating the copper catalyst. [ABSTRACT FROM AUTHOR]

Arylated flavones were prepared by Suzuki-Miyaura reactions of 6-bromo-3-(trifluoro-sulfonyloxy)flavone. The reactions proceeded with very good chemoselectivity in favor of position 3. [ABSTRACT FROM AUTHOR]

Thermal isomerization of bis(spiropyrazolone)cyclopropanes in DMSO at 100 °C results in highly efficient formation of the corresponding 4-[(pyrazol-4-yl)methylene]pyrazolones in 90-98% yields after only five minutes. NMR and single-crystal X-ray diffraction analysis indicate stereoselective formation of the Z-isomers. [ABSTRACT FROM AUTHOR]

Vicarious nucleophilic substitution (VNS) of 3- and 4-nitro(pentafluorosulfanyl)benzenes with phenoxyacetonitrile followed by catalytic hydrogenation provided a two-step, atom-economical synthetic route to 6- and 5-(pentafluorosulfanyl)-1H-indoles. The VNS reaction with chloromethyl phenyl sulfone, nitro group reduction, imine formation, and base-induced cyclization gave efficient access to 2-aryl substituted 6- and 5-(pentafluorosulfanyl)-1H-indoles. Finally, the VNS reaction with ethyl chloroacetate and nitro group reduction followed by thermal cyclization (lactam formation) furnished SF5-containing oxindoles. Their transformation into 2-halo-substituted SF5-indoles was demonstrated. [ABSTRACT FROM AUTHOR]

A simple and efficient protocol promoted by BF3·OEt2 for synthesizing functionalized dibenzothiophenes (DBTs) has been demonstrated. The annulation condition can tolerate a variety of functional groups. [ABSTRACT FROM AUTHOR]

Discrete organic cage molecules have been introduced as molecular building units for highly porous materials. Here, an overview of the author's contribution in this new field is given. [ABSTRACT FROM AUTHOR]

This report describes the synthesis of 4-organoselenylisoxazoles via FeCl3/RSeSeR-mediated intramolecular cyclization of alkynone O-methyloximes. The optimized conditions allowed the cyclization to proceed at room temperature under ambient atmosphere, and the reaction requires a short time to be completed. The reaction conditions tolerated neutral, electron-donating and electron-withdrawing groups present in both substrates, alkynone O-methyloximes and diorganyl diselenides. Treatment of 4-organoselenylisoxazoles with n-butyllithium, followed by trapping with electrophiles, furnished the functionalized isoxazoles in good yields. The obtained products also proved to be suitable substrates for the preparation of 4-bromoisoxazoles via Br/Se exchange reaction. [ABSTRACT FROM AUTHOR]

The hitherto elusive silaisocyanoacetylene molecule (HCCNSi)-a member of the silaisocyanide family-has been synthesized for the first time through the reaction of the silicon nitride radical (SiN) with acetylene (C2H2) in the gas phase under single collision conditions. Compared to the isoelectronic reaction of the cyano radical (CN) with acetylene, the replacement of the carbon atom in the cyano group by an isovalent silicon atom has a pronounced effect on the reactivity. Whereas the silicon nitride radical was found to pass an entrance barrier and adds with the nitrogen atom to the acetylene molecule, the cyano radical adds barrierlessly with the carbon atom forming the HCCH(NSi) and HCCH(CN) intermediates, respectively. These structures undergo hydrogen loss to form the linear silaisocyanoacetylene (HCCNSi) and cyanoacetylene molecules (HCCCN), respectively. Therefore, the isovalency of the silicon atom was found to bear little resemblance with the carbon atom having a dramatic effect not only on the reactivity, but also on the reaction mechanism, thermochemistry, and chemical bonding of the isoelectronic silaisocyanoacetylene and cyanoacetylene products, effectively reversing the thermodynamical stability of the nitrile versus isonitrile and silanitrile versus isosilanitrile isomer pairs. [ABSTRACT FROM AUTHOR]

A simple and efficient procedure for the asymmetric synthesis of (−)-( R)-massoia lactone, ( R)-δ-decalactone, and (+)-(3 R,5 R)-3-hydroxy-1,5-decanolide is described. Verbalactone was synthesized using Heck allylation at the key stage of construction of the carbon skeleton. [ABSTRACT FROM AUTHOR]

A new synthetic strategy for C–C bond formation has been developed via a free radical cascade process under metal-free conditions. Activation of inert C(sp3)–H/elimination of SO2/C–C bond formation were achieved in sequence in this system. [ABSTRACT FROM AUTHOR]

The synthesis of silaheterocycles through the first examples of an intramolecular silene Diels–Alder reaction is described. [ABSTRACT FROM AUTHOR]

Biaryl-based bis(thiourea) was found to be an efficient organocatalyst for the asymmetric Henry reaction. High enantioselectivity of up to 93% ee was obtained for the reaction of nitromethane with aryl aldehydes when the combination of N,O-bis(trimethylsilyl)trifluoroacetoamide (BSTFA) with a catalytic amount of potassium acetate was used as the base. [ABSTRACT FROM AUTHOR]

An enantioselective synthesis of (-)-cis-2-aminomethylcyclopropanecarboxylic acid [(-)-CAMP] has been achieved in 2.5% total yield over ten steps starting from 2-furaldehyde. The synthesis features diastereoselective cyclopropane formation via diazene, followed by oxime formation and the reduction, for construction of the γ-aminobutyric acid (GABA) motif. [ABSTRACT FROM AUTHOR]

This paper studies two-step synthetic process of TEX (4,10-dinitro-2,6, 8,12-tetraoxa-4, 10-diazatetracyclo-[5. 5. 0. 05,9 03,11]-dodecane) and the effects of key factors on the yield of DFTHP (intermediate) and TEX. The results show that the yield of DFTHP could reach to 68. 3% when the adjusted pH value of reaction solution reaches to 9 by saturated NaOH solution. When the volume ratio of fuming HNO3 to concentrated H2SO4 is 3 : 2, and the ratio of nitrating agent (mL) to DFTHP(g) is 3 : 1, the yield of TEX raises to 59. 7% . The optimized overall yield of TEX obtained from two-step synthetic process could be 40. 8%. [ABSTRACT FROM AUTHOR]

The article discusses the study regarding the synthesis of the methyl maleopimarate based 2,3-dienoate compound. Topics include the refluxed of methyl maleopimarate in anhydrous C6H6 with thionylchloride and the identification of isolated compound through various spectral model such as infrared (IR) spectrum and proton magnetic resonance (PMR) spectrum, nuclear magnetic resonance (NMR) spectrum.

Rasagiline is a compound with important neuroprotective activity applicable to the treatment of neurodegenerative diseases. This work describes an easy and straightforward methodology to the synthesis of new propargylated rasagiline analogues derived from commercially available 6,7-dihydro-5H-cyclo- penta[b]pyridine. [ABSTRACT FROM AUTHOR]

(A) A highly stereoselective synthesis of Z-allyl bromides from Baylis-Hillman adducts has been realized using CBr4 and Ph3P. The product can be further elaborated into the natural bioactive fatty acid amides semiplenamides C and E. (B) Selective aerobic photooxidative dibromination of ethyl aromatics to dibromoacetophenones has been achieved using CBr4, visible light and molecular oxygen. (C) CBr4 can participate in atom transfer radical additions to olefins using a visible-light photocatalyst. The 1,1-dibromoalkenes are obtained after further manipulation. (D) Dong et al. reported the preparation of fully substituted isoxazoles from cyclopropyl oximes using a combination of CBr4 and Ph3P as the bromination reagent. (E) Chiral 1,3-oxazoline heterocycles bearing fluorinated aliphatic chains (RF) were obtained from a tandem one-pot reaction promoted by a combination of CBr4 and Ph3P. The product skeleton is present in many bioactive molecules, natural products, organomaterials and ligands for asymmetric catalysis. (F) In the presence of CBr4, dithiocarbamates and thioethers were prepared by reaction of dithioic acids, generated in situ, or thiols with nucleophiles such as active methylene compounds or N-methyl indole at room temperature. (G) Benzoxanthenes owning spectroscopic properties for leuco dyes, laser technology and fluorescent materials can be prepared us- ing CBr4 as the catalyst under solvent-free conditions. [ABSTRACT FROM AUTHOR]