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Substituted aromatic amides reacted efficiently with allylic acetates in the presence of a cationic ruthenium complex in ClCH2CH2Cl at room temperature providing ortho allylated benzamides in a highly regioselective manner without any oxidant and base. The whole catalytic reaction occurred in a Ru(II) oxidation state and thus the oxidation step is avoided. By tuning the reaction temperature, ortho allyl and vinyl benzamides were prepared exclusively. Later, ortho allyl and vinylated benzamides were converted into biologically useful six- and five-membered benzolactones in the presence of HCl.

Lewis acid-catalyzed reactions of 2-substituted cyclopropane 1,1-dicarboxylates with 2-naphthols is reported. The reaction exhibits tunable selectivity depending on the nature of Lewis acid employed and proceed as a dearomatization/rearomatization sequence. With Bi(OTf)3 as the Lewis acid, a highly selective dehydrative [3+2] cyclopentannulation takes place leading to the formation of naphthalene-fused cyclopentanes. Interestingly, engaging Sc(OTf)3 as the Lewis acid, a Friedel-Crafts-type addition of 2-naphthols to cyclopropanes takes place, thus affording functionalized 2-naphthols. Both reactions furnished the target products in high regioselectivity and moderate to high yields.

The transition-metal-free procedure for the three-component coupling of aziridines, arynes and aldehydes affords N-aryl α-amino epoxides in moderate to good yields and diastereoselectivities.

Synthesis of new air stable octahedral ruthenium(II) carbonyl complex bearing O, and N-bidentate benzhydrazone ligand is reported. It has been characterized by elemental analysis, spectral methods and single crystal X-ray diffraction method. The new catalyst has been effectively applied to the transfer hydrogenation reaction of various ketones using isopropanol as a solvent and KOH as a base at 82 °C and the maximum conversion is achieved up to 100%.

A highly efficient synthesis of benzoimidazo[1,2-a]imidazolone through a novel oxidative 5-exo-dig cyclization-ketonization cascade of 2-aminobenzimidazole, aldehyde and terminal alkyne has been explored under aerobic conditions. The reaction proceeds through copper-catalyzed addition of terminal alkynes to imines derived from 2-aminobenzimidazole with aldehyde followed by intramolecular cyclization. The atmospheric molecular oxygen acts as an oxygen source for the newly formed carbonyl group in the final product.

An expeditious and novel strategy has been explored for the synthesis of structurally diverse indole-fused diazocine and diazepine derivatives. A substrate-based diversification approach of methyl-3-aminoindole/indoline benzoates coupled with the Pictet–Spengler reaction and three different reaction cascades furnished indolodiazepine and indoloquinoxalines. The formation of indolodiazocines proceeds through an initial condensation followed by intramolecular alkylation.

The aryne multicomponent coupling involving carboxylic acids initiated by aziridines as nucleophiles affords N-aryl β-amino alcohol derivatives while the application of azetidines as nucleophilic triggers furnishes N-aryl γ-amino alcohol derivatives.

A highly regioselective ortho-allylation using the ketoxime substituent as directing group is presented.

New rhodium(I) complexes [Rh(CO)(L)] ( 1 – 3 ) were prepared by the reaction of [RhCl(CO)(PPh 3 ) 2 ] with 9,10-phenanthrenequinone-N-substituted thiosemicarbazones (HL 1-3 ) and characterized by elemental and spectral analyses (IR, UV–Vis, 1 H and 13 C NMR, ESI-Mass). The structure of the complex, [Rh(CO)(L 1 )] ( 1 ) has been established by single-crystal X-ray diffraction analysis. The structure has also been optimized by DFT method using LANL2DZ basis set. The synthesized complexes used as catalysts for the diastereoselective nitroaldol reaction of benzaldehyde with nitroethane in presence of ionic liquid at room temperature. The optimized catalyst 2 was found efficient in the asymmetric Henry reaction between various aromatic aldehydes and nitroalkane. The reusability of the catalyst was checked up to five catalytic runs. The result shows marginal loss in yield and the product retains the diastereoselectivity. It is believed that this procedure provides an opportunity for facilely synthesize of large amounts of diastereomerically enriched β -nitroalcohol.

A simple and novel protocol for the facile synthesis of complex angularly substituted tetracyclic and pentacyclic hybrid molecular frameworks containing a coumarinopyranpyrazole/pyrimidinedione and coumarin ring systems via a solid-state melt reaction (SSMR) through a domino process is developed.

A copper(II)-promoted intramolecular C–H coupling reaction between indole-2 and imidazole-2 moieties has been developed for polycyclic heteroarene synthesis. The method provides direct access to biheteroaryl incorporated polycyclic frameworks, which are of huge interest in the area of functional materials and drug-discovery.

The title reaction gives 2-quinolinones in good yields tolerating diverse functional groups.

The reaction of arynes with indene/benzofurans has been developed. The arynes were generated from 2-(trimethylsilyl)aryl triflates by the fluoride-induced 1,2-elimination react with indene or various benzofurans proceeding via a cascade reaction involving the Diels–Alder reaction and a [2 + 2] cycloaddition reaction. The tandem process afforded functionalized dihydrobenzocyclobutaphenanthrenes in moderate to good yields. Moreover, the method has been utilized for the one-pot synthesis of benzo[b]fluoranthene.

A new procedure for the mild, practical, and scalable Diels—Alder reaction of tropones with arynes is reported.

Optimized reaction conditions are elaborated for the synthesis of triazoloquinazolinones from azides (I) and alkynes via 1,3-dipolar cycloaddition followed by intramolecular amidation.

Transition-metal-free multicomponent reactions involving arynes and isocyanides with either CO2 or H2O have been reported. With CO2 as the third component, the reactions resulted in the formation of N-substituted phthalimides. The utility of water as the third component furnished benzamide derivatives in moderate to good yields. These reactions took place under mild conditions with broad scope.

Acetanilides react with symmetrical and unsymmetrical alkynes in the presence of a Ru/Ag catalytic system in a regio- and stereoselective manner providing ortho-alkenylated acetanilides.

The Ru-catalyzed homo- and heterodimerization of propiolates proceeds with high regioselectivity.

A total of nine different hydroxyquinoline-thiosemicarbazone complexes are prepared revealing similar catalytic activities.

In classical and quasiclassical trajectory chemical dynamics simulations, the atomistic dynamics of collisions, chemical reactions, and energy transfer are studied by solving the classical equations of motion. These equations require the potential energy and its gradient for the chemical system under study, and they may be obtained directly from an electronic structure theory. This article reviews such direct dynamics simulations. The accuracy of classical chemical dynamics is considered, with simulations highlighted for the F− + CH3OOH reaction and of energy transfer in collisions of CO2 with a perfluorinated self-assembled monolayer (F-SAM) surface. Procedures for interfacing chemical dynamics and electronic structure theory computer codes are discussed. A Hessian-based predictor–corrector algorithm and high-accuracy Hessian updating algorithm, for enhancing the efficiency of direct dynamics simulations, are described. In these simulations, an ensemble of trajectories is calculated which represents the experimental and chemical system under study. Algorithms are described for selecting the appropriate initial conditions for bimolecular and unimolecular reactions, gas-surface collisions, and initializing trajectories at transition states and conical intersections. Illustrative direct dynamics simulations are presented for the Cl− + CH3I SN2 reaction, unimolecular decomposition of the epoxy resin constituent CH3NHCHCHCH3 versus temperature, collisions and reactions of N-protonated diglycine with a F-SAM surface that has a reactive head group, and the product energy partitioning for the post-transition state dynamics of C2H5F HF + C2H4 dissociation. © 2012 John Wiley & Sons, Ltd.

Unsymmetrically substituted alkynes (XIII) are found to regioselectively react in a fashion where the less hindered C-H bond of the aromatic nitrile is preferably attacked by the alkyl substituted site of the alkyne.

Benzimidazole linked ortho-chloroamines (I), synthesized from 4-fluoro-3-nitrobenzoic acid, react with various acid chlorides (II) and isothiocyanates (IV) forming ortho-chloro anilides or thioureas, respectively.

Nanocrystalline Li4Ti5O12 is synthesized in less than one minute by a solution-combustion method from an aqueous mixture of TiO(NO3)2, LiNO3, and glycine (alumina crucible, 800 °C) and characterized by powder XRD, SEM, TEM, and electrochemical measurements.

The title compound, C23H15Cl2NO3, crystallizes with two independent mol­ecules in the asymmetric unit. The chroman­one moiety consists of a benzene ring fused with a six-membered heterocyclic ring which adopts a sofa conformation. The five-membered spiro­isoxazoline ring is in an envelope conformation. The p-chloro­phenyl rings bridged by the five-membered ring are nearly perpendicular to each other. The chromanone moiety of one mol­ecule packs into the cavity formed by the p-chloro­phenyl rings of a second mol­ecule through the formation of C—H⋯π interactions. The structure is stabilized by weak C—H⋯O, C—H⋯Cl and C—H⋯π interactions.

4-Hydroxy coumarin and its benzo-analogues undergo intramolecular domino Knoevenagel hetero Diels–Alder reactions with O-prenylated aromatic aldehydes and the aliphatic aldehyde, citronellal to afford pyrano fused polycyclic frameworks. A high degree of chemoselectivity was achieved by the application of microwave irradiation.

Fulvenes acting as 4π components in an intramolecular [4+2] cycloaddition reaction leading to the formation of novel 6-oxatricyclo [6.4.0.02,10] dodeca-2,11-diene ring systems have been described. Importance of steric buttressing effect in promoting the reaction has been discussed.

Synthesis of a series of novel spiroisoxazolines[5.9']anthrone by regioselective 1,3-dipolar cycloaddition reaction of nitrile oxides with 9-arylidene anthrone is described.

Synthesis of a series of novel spiro[3,4-diaryl-4,5-dihydroisoxazole-5,31-flavan-41-one] has been accomplished in good yields by the regioselective 1,3-dipolar cycloaddition reaction of nitrile oxide to 3-arylmethylidene flavan-4-ones.