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A AgSbF6-catalyzed cascade involving the ring opening of donor–acceptor cyclopropanes (DACs) preceded by the cyclization of N-protected 2-ethynylaniline is described. The method discloses a step-economy route to 2,3-disubstituted indole, where a Ag catalyst is found to trigger the cascade by activating both alkyne and DACs. Various functionalities at different ends of both substrates offer rapid access to 2,3-disubstituted indole derivatives in one pot in good to excellent yields. Elaboration of the cascade product to useful intermediates is also depicted.

A simple, convenient and efficient p-toluenesulfonic acid catalyzed tandem reaction of aliphatic ketones with substituted anilines towards the synthesis of polysubstituted 1,2-dihydroquinolines has been developed. The ready availability of the catalyst, operational simplicity, cost effectiveness of the process and excellent regioselectivity mark some of the highlights of this methodology.

A ligand- and base-free, Pd-catalyzed protocol to access a wide range of symmetrical and unsymmetrical biaryls from stable diaryliodonium salts was developed. The reaction involved the use of an effective and recyclable Pd/polyethylene glycol-400 catalyst system to harness the aryl moieties of two diaryliodonium salts; the ensuing biaryls may be utilized to synthesize an array of useful compounds, including 5-aryluracils, carbazoles, chromenones, fluorenones, phenathridines, and boscalid analogues.

Stereoselective total synthesis of unnatural (+)-anisomycin from d -glucose has been achieved with an overall yield of 23%. The key synthetic features are regioselective opening of an epoxide, azidation of the resulting alcohol, and finally one-pot hydrogenation leading to cyclization to the pyrrolidine ring in a single step.

N,N-Dihalosulfonamides are important reagents for various organic transformations. Simplicity, efficiency, and a unique chemical behaviour make this class of compounds synthetically useful. N,N-Dibromo-p-toluenesulfonamide (TsNBr2) is an efficient source of electrophilic bromine, which, at the same time, also provides the nucleophilic sulfonamide counterpart to form a C–N bond. This reagent has also been found to be a suitable precursor of nitrene. These diverse properties led to the development of various important organic transformations under catalyst-free and relatively mild reaction conditions. However, the strong oxidizing nature of this reagent sometimes appears as a limitation for a desired functional group transformation. 1 Introduction 2 Cohalogenation of Olefins 3 Activation of Alkynes with TsNBr2 4 Oxidation Reactions 5 Nitrene Transfer Reactions 6 Hofmann Rearrangement Using TsNBr2 7 Bromination of Aromatic Compounds 8 Cleavage of Oximes 9 Miscellaneous Reactions 10 Conclusion

meta-Hydroxylated cores are ubiquitous in natural products. Herein, we disclose the first template assisted meta-hydroxylation reaction. Experimental and in silico studies helped us to gain valuable mechanistic insights, including the role of the hexafluoroisopropanol (HFIP) solvent, during C–H hydroxylation. The reactive intermediates, prior to the C–H activation, have been detected by spectroscopic techniques. Additionally, the C–O bond formation has been extended to meta-acetoxylation. The preparation of a phase II quinone reductase activity inducer and a resveratrol precursor illustrated the synthetic significance of the present strategy.

Bromination is one of the most important transformations in organic synthesis and can be carried out using bromine and many other bromo compounds. Use of molecular bromine in organic synthesis is well-known. However, due to the hazardous nature of bromine, enormous growth has been witnessed in the past several decades for the development of solid bromine carriers. This review outlines the use of bromine and different bromo-organic compounds in organic synthesis. The applications of bromine, a total of 107 bromo-organic compounds, 11 other brominating agents, and a few natural bromine sources were incorporated. The scope of these reagents for various organic transformations such as bromination, cohalogenation, oxidation, cyclization, ring-opening reactions, substitution, rearrangement, hydrolysis, catalysis, etc. has been described briefly to highlight important aspects of the bromo-organic compounds in organic synthesis.

Perovskite oxide La0.3Sm0.2Sr0.5Ti0.5Fe0.5O3 has been synthesized by a citrate-gel precursor method. The Rietveld analysis of the XRD data showed that the sample crystallizes with a orthorhombic structure in the space group Pbnm. Magnetic properties suggest that antiferromagnetic interactions are dominant due to Fe3+–O–Fe3+ units.

An organocatalytic enantioselective reaction of 2-methylcyclopentane-1,3-dione, nitroalkene, and α,β-unsaturated aldehyde with the diphenylprolinol catalyst was developed to give the highly functionalized Hajos–Parrish-type ketones with five to six contiguous stereocenters and two quaternary carbon stereogenic centers with high diastereoselectivity and enantioselectivity. The structures of the adducts were unambiguously confirmed by single-crystal X-ray crystallographic analyses of the appropriate products.

A metal free cross coupling of aryl alkyl ketones with alkyl/aryl H-phosphonates and H-phosphine oxides using tetrabutylammonium iodide (TBAI) catalyst in the presence of tert -butyl hydroperoxide (TBHP) as terminal oxidant in aqueous media is developed. This new approach offers a direct and convenient route to access a wide range of ketol phosphates and phosphinates in moderate to good yields.

A one-pot, three-component synthesis of widely substituted isoindolinones and isoquinolinones, featuring a Lewis acid-catalyzed efficient Strecker reaction and lactamization sequence, affording products in good to high yields is reported. The method has also been extended to the synthesis of tetrahydroisoquinolines (THIQs) in high yields.

Substituted oxocene derivatives have been synthesized by Lewis acid catalyzed reactions of e-hydroxyalkene and substituted aromatic aldehydes. The Cu(OTf)2-bis-phosphine catalyzed reaction typically provides substituted dihydropyran derivatives through an olefin migration followed by a Prins cyclization. The corresponding reaction catalyzed by TMSOTf or BF3·OEt2 provided eight-membered cyclic ethers (oxocenes), selectively. This methodology provides convenient access to a variety of 2,4,8-trisubstituted oxocenes in good yields and excellent diastereoselectivities.

Among the title isoxazoles (II) and pyrazoles (IV), compound (IIi) shows the highest cytotoxic potential towards the COLO320 cancer cell lines.

An efficient and rapid protocol for the synthesis of 3,4-disubstituted and 3,4,5-trisubstituted isoxazoles under catalyst-free conditions is described. This protocol involves pre-oxidation of aldoxime into nitrile oxide using diacetoxyiodobenzene. The in situ generated nitrile oxide was trapped with dipolarophiles for the formation of functionally rich isoxazoles via [3+2] cycloaddition.

The direct coupling of sp3 C–OH bond of N-heterocyclic aminols with sp2 C–H bond of electron rich arenes have been achieved via iron catalyzed dehydrative cross coupling strategy. This novel protocol provides an efficient and straight forward route to access biologically important C4-aryl-3,4-dihydroquinazoline derivatives through the reaction of C4-hydroxy-3,4-dihydroquinazoline/aminol with phenol and aniline derivatives under mild reaction conditions.

Polystyrene-supported palladium(0) (Pd@PS) nanoparticles as a heterogeneous catalyst have been developed for caboxylation of aryl halides, alkenylsilanes, and organoboronic acids to produce the corresponding carboxylic acids with minor quantities of corresponding aldehydes using bench-stable and inexpensive oxalic acid as the C1 source under focused microwave irradiation. The close vicinity of oxalic acid to Pd@PS maintained through ionic bonding helped to produce CO2 over the catalytic surface that concurrently participated in the carboxylation reaction.

An efficient approach for the synthesis of 1,3-diketones from aldehydes and ketones has been developed using Bu 4 NI (TBAI) as the catalyst. In the presence of DTBP–TBHP/ p -TsOH, aldehydes undergo radical coupling with ketones to provide the desired products in moderate to high yields at 120 °C. Although various substituents on the aromatic ring of aldehydes are well tolerable under the standard reaction conditions, the protocol is limited by the scope of ketones. The method exhibits advantages in terms of the easy access of the starting materials, operational simplicity, functional group tolerance, and the absence of metal catalyst.

An efficient and facile synthesis of divergent C-3/C-5 bis-functionalized 2-oxindole derivatives has been achieved from 3,5-bis-Morita-Baylis-Hillman (MBH) adducts of oxindole via nucleophilic substitution reaction for the first time. Wider scope of substrate and rate acceleration has been observed in second MBH reaction under typical reaction condition. The synthetic usefulness of bi-functionalized bis-allyl derivative has been demonstrated by the synthesis of potent bis-pyrazole via [3 + 2]-annulation strategy.

Excellent selectivity for terminal attack of the diene component is observed except for reactions involving o-substituted aniline components like (IX).

Antimicrobial agents 4a–g and 5a–g with very good potency were synthesized with 100% ee from phenylpropanolamine (norephedrine) by BF3 catalyzed three components one pot Mannich reaction in good yields. Obtained compounds were characterized using spectral techniques. Antimicrobial study of these compounds revealed a good to very high potential activity against tested microbes when compared to standard antimicrobial drugs streptomycin and ketoconazole. These synthesized compounds exhibited significant minimum inhibitory concentration (MIC) values against Gram positive and Gram negative bacteria. Amongst compound 4b, 4c, 4d, 4e, 5a, and 5e exhibited very high potent MIC values against tested twelve bacteria and three fungi when compared to control. When subjected to molecular docking, in silico studies revealed significant binding energies ranging from −7.06 to −8.90 kcal/mol for all obtained compounds towards target receptor DNA topoisomerase IV and amongst compounds 4b and 4d have shown maximum binding energies 8.70 and 8.90 kcal/mol, respectively.

One-pot synthesis has become an important subject of modern synthetic chemistry owing to its efficiency, versatility and expediency in constructing complicated polycyclic ring systems, especially with a sustainable and catalytic aspect. This review aims to highlight the recent advances in this area with specific emphasis on the asymmetric synthesis of natural products and related core structures as well as medicinal drugs via one-pot operation. 1 Introduction 2 Double Reactions 3 Triple Reactions 4 Quadruple Reactions 5 Pot-Economy Reactions 6 Conclusions

An efficient diversity oriented synthesis of [1,2,3]triazolo[1,5-a][1,4]benzodiazepines has been developed by sequential diazotization, azidation and cycloaddition reactions in a one-pot fashion. This strategy allows an easy accessibility of triazole fused [1,4]benzodiazepines in good yields. The main objective of this methodology is to introduce various substituents at all possible positions under mild reaction conditions. All the synthesized compounds were evaluated for their antimicrobial, anticancer and in silico activity. Among the tested compounds (2a–n), the derivatives 2a, 2b, 2d, 2k, 2g, 2j, 2m and 2l have displayed a broad spectrum of antibacterial activity. Anticancer activity results revealed that compounds 2a, 2g and 2m exhibited potent in vitro anticancer activity against A549 lung adenocarcinoma cancer cell line. Further, molecular docking studies of all the synthesized compounds were performed to gain a comprehensive understanding of the plausible binding modes and also to compare the theoretical and experimental results of these compounds.

Using an o-cyanophenoxy group as directing group benzylsulfonic acid esters are olefinated in meta-position by terminal and internal olefins.

An efficient, catalyst-free methodology has been developed for the Michael addition reaction between d -glucosamine derivatives and various Michael acceptors. All reactions proceeded smoothly at room temperature to furnish novel sugar-derived vinylogous carbamates in high chemical yields and excellent stereoselectivity.

Direct α-arylchalcogenation of acetone with diaryl dichalcogenides has been achieved by using a mixture of TBHP and DTBP oxidants at 120 °C without transition-metal catalyst via oxidative C(sp3)–H bond functionalization. The method exhibits good functional group tolerance and products were isolated in moderate to high yields.

A novel and efficient synthesis of a variety of isoindolinones and tetrahydroisoquinolines via a Lewis acid catalyzed domino Mukaiyama–Mannich lactamization/alkylation is achieved. This transformation comprises a sequential formation of three new bonds through a one-pot, three-component procedure to afford product in moderate to high yields. A concise synthesis of (±)-homolaudanosine (2b) has been achieved using this method.

Decarboxylative functionalization of α,β-unsaturated carboxylic acids is an emerging area that has been developed significantly in recent years. This critical review focuses on the different decarboxylative functionalization reactions of cinnamic acids leading to the formation of various C–C and C–heteroatom bonds. Apart from metal carboxylates, decarboxylation in cinnamic acids has been achieved efficiently under metal-free conditions, particularly via the use of hypervalent iodine reagents. We believe this review will encourage organic chemists to develop vinylic decarboxylation in a more appealing way with an understanding of new mechanistic insight.

Starting from various methyl 2-formyl benzoates, hydroxyacetone and aryl amines the scalable title reaction is elaborated providing the products in high yields, with high dia- and enantioselectivity.

Several commercial Lewis acids, specifically TiCl4, were able to promote the condensation reaction between aromatic bisulfite adducts and 2,4-thiazolidinedione to produce 5-arylidene derivatives. The product distribution was not affected by the equivalents of TiCl4 used, but was dependent on temperature and the nature of the solvent medium. In all cases, the reaction required activation of the aromatic bisulfite adducts by Lewis acids, followed by the loss of SO2 and subsequent regeneration of the parent aldehyde. The in situ formed aldehyde ultimately underwent acid-catalyzed carbon–carbon bond formation to give 5-arylidene derivatives. The reaction with TiCl4 afforded the products from aromatic and aliphatic bisulfite adducts in moderate to good yields. When hydrated Lewis acids were used, in addition to 5-arylidenes, the in situ formed aldehyde underwent a disproportionation reaction to give a carboxylic acid as a by-product.

Title compounds (II) are synthesized using easily accessible reagents and simple reaction conditions.

Nitroalcohols are prepared by Henry reaction of aldehydes with nitromethane using Ambersep 900 OH anionic ion-exchanger resin as catalyst.

A highly anti-Markovnikov-selective oxidation of alkenes based on in situ generated hypoiodite catalysis in aqueous micellar media under mild conditions is described.

The tedanolides are biologically active polyketides that exhibit a macrolactone constructed from a primary alcohol. Since polyketidal transformations only generate secondary alcohols, it has been hypothesized by Taylor that this unique lactone could arise from a postketidal transesterification. In order to probe this hypothesis and to investigate the biological profile of the putative precursor of all members of the tedanolide family, we embarked on the synthesis of desepoxyisotedanolide and its biological evaluation in comparison to desepoxytedanolide. The biological experiments unraveled a second target for desepoxytedanolide and provided evidence that the proposed transesterification indeed provides a survival advantage for the producing microorganism.

A new unified strategy has been developed for the synthesis of substituted 2-alkenylindoles and carbazoles. The strategy uses palladium-catalyzed α-arylation of TES-enol ethers of enones as the key step. The method is highly regioselective, provides good yields, and is expected to have wide application.

Homoallylic alcohols (III), (V) are obtained by allylation of the various substituted aldehydes or ketones using high purity Sn(0) as catalyst.

A long persistent, transparent, flexible, and water resistant phosphorescent layer of sunlight-activated green luminescent Sr1-x-yAl2O4:Eux 2+/Dyy3+ (x = 0.05—0.3, y = 0.1—0.6) is fabricated via solid state reaction/solution casting of SrCO3, Al2O3, Eu2O3, and Dy2O3 (10% H2/N2 atmosphere, alumina crucible, 1300 °C, 3 h).

Methylation is one of the most fundamental synthetic transformations in organic chemistry, but usually employs hazardous and toxic reagents, such as methyl iodide, dimethyl sulfate, diazomethane and dimethyl carbonate. In order to address sustainable development and green strategies, synthetic chemists have devoted much effort to the discovery and development of new methylating reagents, which are successfully being applied in transition metal-catalyzed cross-coupling reactions. In this review, recent advances in this area are summarized, mainly including C-methylation, N-methylation and O-methylation. The respective reaction mechanisms are also discussed.

An efficient nitrene transfer process to arenes using azides under metal free conditions is reported.

Ervatamine, silicine, methuenine, etc., are naturally occurring alkaloids that exhibit antimicrobial, anticancer, and anti-HIV activities. Indole fused with a seven-membered carbocyclic ring is a commonly observed structural feature among this series of bioactive compounds. This work describes a strategic approach for the synthesis of cyclohepta[b]indole structural scaffolds. The synthetic strategy consists of a solvent-free Baylis-Hillman reaction of 2-bromobenzaldehydes, followed by iodine-catalyzed C-alkylation of indole with the Baylis-Hillman adducts. Finally, intramolecular Heck coupling reaction using Pd(OAc)2 as catalyst in the presence of benzyltrimethylammonium bromide under microwave condition produced the desired cyclohepta[b]indole derivatives.

This review describes the synthesis of different water soluble polythiophenes and their versatile applications. Solubility in water is essential for developing sensors for different bio-molecules and polythiophene derivatives are excellent candidates due to their important optoelectronic properties. A pristine polythiophene chain is hydrophobic and it exhibits aqueous solubility after attachment/grafting of ionic pendent groups or hydrophilic polymer chains on its backbone. A concise account of the different synthetic procedures of preparing water soluble polythiophene is described and all the specific techniques relevant to the synthesis of water soluble polythiophene using cationic, anionic pendent groups and grafting of hydrophilic polymers are discussed. Different grafting processes e.g. “grafting from” and “grafting to” techniques using click chemistry and atom transfer radical polymerization (ATRP) are described in detail. Detections of different bio-molecules such as DNA, RNA, polypeptides, polysaccharides, ATP, UDP and ADP from the excellent opto-electronic properties of aqueous polythiophenes are discussed. The reports on fluorescence based specific sensing of metal ions, and nitro-aromatics using water soluble polythiophenes are also embodied with an up-to-date description of the optoelectronic device applications such as logic gates, molecular thermometers, photovoltaic cells etc. Finally, a summary and outlook is presented discussing the future scope of research on this important subject.

The advantages of the introduced methodology are mild reaction conditions, cleaner reaction profile, operational simplicity and cheap, non-toxic and readily available catalyst.

Sharpless asymmetric dihydroxylation of tetrahydropyridines (II) affords the expected diols in high yields but only very poor enantioselectivity.

The reactions can also be performed using Zn(OTf)2 or Cu(OTf)2 for the synthesis of isoindoles or isoquinolines, respectively.

Structurally diverse C-4-amidyl- and C-4-phosphonyl-3,4-dihydroquinazoline derivatives (III)/(V) are efficiently obtained via dehydrative cross-coupling reaction utilizing either an inexpensive iron catalyst or metal-free conditions.