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Research has been conducted on 1-arylnaphthalene ligands. The authors describe the synthesis of nitrogen-containing 1-arylnaphthalene ligands' heterocyclic analogues, and the Pummerer reaction-based generation of furo[3,4-c]pyridines.

Research has been conducted on (+)-anhydrochatancin. The authors describe the synthesis of this compound which has led to enantioselective synthesis of (+)-chatancin.

Research has been conducted on allocolchicinoids. The authors have developed the strategy for the synthesis of ring C functionalized allocolchicinoids based on Diels-Alder reacion-aromatization sequence.

Research has been conducted on enynes. The preparation of these compounds from 1-(triphenylphosphoranylideneaminoalkyl)benzotriazoles is described.

Research has been conducted on Diels-Alder reactions. The authors have investigated the hypothesis that Diels-Alder reaction rates depend on the solvent media viscosity, and have presented the results.

Research has been conducted on N-3,5-hexadienoyl ethyl acrylimidates. Results demonstrate that intramolecular Diels-Alder reaction of these compounds allows for the synthesis of cis-fused hexahydroisoquinolones.

Research has been conducted on catalysts which contain bisoxazoline or phosphinooxazoline ligands inducing asymmetry during the Diels-Alder reaction. The authors describe the use of Comparative Molecular Field Analysis developed for these catalysts.

The authors describe the reactions between isoprene and dichloropropynylborane. The authors report the use of density functional theory method applied to the reaction processes involving Diels-Alder cycloaddition and 1,4-alkynylboration in investigating these reactions.

Research has been conducted on Diels-Alder reactions between cyclopentadiene and mono-, di-, tri- and tetracyanoethylene. The authors report the study of transition structures for these reactions carried out via DFT methods.

Research has been conducted on 3,6-bis(3,4-dimethoxybenzoyl)-1,2,4,5-tetrazine. The authors describe the synthesis of this compound and its reactivity in inverse demand Diels-Alder reactions.

Research has been conducted on N-carbobenzyloxy-o-iodoanalines. The authors report the results of palladium-catalyzed heteroannulation of these compounds with 1-phenylthio-1,3-butadiene which has led to indolines.

Research has been conducted on 4-iodo-1.1.2.2.9.9.10-octafluoro[2.2]paracyclophane. The authors report that dehydroiodionation of this compound and double dehydroiodionation of a mixture of 4,15- and 4,16-diiodo-1,1,2,2,9,9,10,10-octafluoro[2.2]paracyclophane has led to Diels-Alder trapping of intermediate arynes.

Research has been conducted on Diels-Alder reaction rate constants. The authors report that these constants of methyl vinyl ketone with cyclohexadiene and cyclopentadiene have been measured in the presence of an organotungsten catalyst and modeled theoretically at different temperatures.

Research has been conducted on intramolecular Diels-Alder reactions of 2-azadiene models. The authors report the results of quantum chemical studies of these models carried out in investigating stereochemical features of the cyclization involved in paraherquamide A biosynthesis.

Research has been conducted on 2-phenyl-3,4-dimethyl-5H-phosphole. The authors report that the reaction of this compound with aldehydes has led to [4+2] P-O cycloadducts with endo- and exo-R-substituents.

Research has been conducted on trans-trans-trans macrocyclic trienes. The study of these compounds carried out via the use of Diels-Alder reaction is described.

Research has been conducted on semicyclic dienes with secondary and tertiary allylic magnesium alkoxide alcohol functionality. The authors desribe the stereocontroled Diels-Alder reaction of these dienes, and report the details.

Research has been conducted on dehydro Diels-Alder reactions. The study of the cyclic allene intermediate evolution carried out via theoretical and experimental investigation of these dehydro Diels-Alder reactions in order to examine intramolecular, ionic and radical intermolecular cycloaromatization processes is presented.

The authors describe the synthesis of chiral furanyl and pyranyl dienes. They report that this synthesis is based on cycloalkenation of chiral tungsten alkynol complexes.

Research has been conducted on cyclohex-3-ene-1,1-bis(phosphonates). The authors demonstrate that this compound can be obtained during the reactions of tetraethyl vinylidenebis(phosphonate) with substituted 1,3-dienes without solvent.

Systematic comparisons between broken symmetry (BS) and symmetry-adapted (SA) approaches to transition states were carried out using chemical indices using the occupation numbers of natural orbitals by both BS and SA methods. The computational results for the Diels-Alder and the core rearrangement reactions have indicated that the current procedures are promising for pericyclic reactions in general.

Research has been conducted on unfunctionalized conjugated diene and nitroarene. The reaction between these compounds has been carried out in the presence of CO, and the results demonstrate that it leads to hetero-Diels-Alder adducts.

Research has been conducted on Diels-Alder acylnitroso cycloadduct and cyclopentenyl acetate-derived allylindium(III). The authors demonstrate that these species have been generated from in situ palladium(0) catalysts and indium(I) iodide.

Research has been conducted on 2,2-bis(trifluoromethyl)-1,1-dicyanoethylene. The authors describe the reactions of this compound with 6,6-dimethylfulvene, and report that this reaction leads to Diels-Alder cycloadduct which is unstable and exists in equilibrium with the starting materials in less polar solvents.

Research has been conducted on new class of ligands. The authors report that the design and preparation of these ligands is based on the sulfinyl imine functionality.

Research has been conducted on o-quinone methides generated from OBOC-salicy lic alcohols and aldehydes . The results of the Diels-Alder reactions of these compounds which lead to the synthesis of different substituted benzopyrans are described.

The synthesis, structure and unique dynamic behavior of halogen-substituted cyclotrigermenes as well as facial selectivity in the Diels- Alder reactions with butadiene are reported. The butadiene attacks the Ge=Ge double bond from the site of the more bulky (super t)Bu3Si group in contrast to mesityl- substituted cyclotrigermene.

A study of the dimerization of cyclopentadine, which unexpectedly disclosed the origin of the endo selectivity and led to a simple rationalization, is reported. The result states that the endo Diels-Alder Transition Structure (DATS) of cyclopentadiene dimerization is admirably suited to take advantage of the maximum accumulation of unsaturated centers.

Diels-Alder cycloaddition of s-trans-1,3-butadiene should yield trans-cyclohexene, just as reaction of the s-cis conformer gives cis-cyclohexene. It is concluded that full understanding of the Diels-alder reaction requires consideration of both conformers of 1,3-butadene.

A six step formal total synthesis of a natural alkaloid, mappicine is achieved. The highlight of synthetic strategy is an intramolecular hetero Diels-Alder reaction that was used for the construction of the CD ring system of mappicine.

The efficient synthesis of methyl sarcophytoate via the intermolecular Diels-Alder reaction is presented. The absolute configuration is confirmed by the total synthesis.

The Diels-Alder reaction was employed to chemically modify the two-dimensional monolayer (SAM) surfaces, which includes the monolayer-protected gold nanoparticles (MPNs). The analysis reveals that various hyperbaric pressure conditions can be used to facilitate such reactions.

The competing Diels-Alder (DA) reactions including two different dienes have unsymmetrical bis-pericyclic transition state that leads predominantly to one of the possible products and the shape of the potential energy surfaces (PES) and major product are both reversed by Lewis acid (LA) catalysts. The competing DA and hetero-DA reactions and shifts in product ratios by acid catalysis are studied by using the single malleable bis-pericycle transition state.

The highly catalytic enantioselective nitroso hetero-Diels-Alder reaction is reported. This reaction could provide one of the effective synthetic routes to a number of chiral 1,4-diamines that are pharmaceutically important compounds.

A convergent, dual-cycloaddition approach to the hetisine alkaloids, illustrated by an exceedingly concise synthesis of the antiarrhythmic agent nominine is reported. It is revealed that rapid synthesis access into the hetisine skeleton should pave the way for the construction of other, more highly oxidized, members of the C20-diterpeniod alkaloids such as the antiarrhythmic guanfu bases.

An efficient protocol for the synthesis of eight-membered bicyclic compounds through 1,2,4Z,7-tetraenes is described. The reaction is found to proceed through the sequential [2 + 2] cycloaddition, [1,5]-H migration, and electrocyclic rearrangement or the sequential [1,5]-H shift and 8pi-electrocyclic reaction.

A study is conducted to demonstrate that there are three basic reactions for the alkynes with arynes, namely dehydro Diels-Alder reaction (DDAR), ene, and acetylenic C-H addition reactions. These provide simple and efficient routes for the synthesis of various phenanthrene, phenylallene, and phenylalkyne derivatives.

An undemanding preparation of [4]-dendralene is reported, employing standard laboratory equipment. Methods to control the regio-chemical outcomes of Diels-Alder reaction sequences involving [4]dendralene are revealed.

A study is conducted to demonstrate that electron poor dienes and oxadines participate in (4+1)-cycloadditions with dialkoxy carbenes. The [4 + 1] cycloaddition between a carbene and a diene to give a cyclopentene derivative is the five-membered ring equivalent of the Diels-Alder reaction.

Novel copper (I) Lewis acid catalyst, relying on planar chiral 1-phophino-2-sulfenylferrocence show excellent activity, enantioselectivity and structural scope in asymmetric ADAR between N-sulfonylaldimines type of dienes. The mechanistic origin of the high enantiocontrol and the extension of this study to other heterodienophiles and dienes are under investigations.

The first total synthesis of (+)-macquarimicin A is accomplished with 27 linear steps. The transannular Diels-Alder reaction, which constructed the tetracyclic framework of (+)-macquarimicin A stereoselectively, is featured in the synthesis.

Heavier group 14 element alkene analogues react with dienes to give cycloaddition products in a manner similar to the Diels-Alder reaction. Data suggests the possibility of isolating an aluminium species of formula RAlAlR and the study of addition reactions to the Al-Al double bond.

The effort to expand the scope of phosphine-catalyzed annulations has led to the discovery of a new class of 1,4-dipole synthons, 2-alkyl-2,3-butadienoates. The importance of the finding is exemplified by the expedient [4+2] annulation reaction with N-tosylaldimines to form tetrahydropyridine derivatives in excellent yields with complete regioselectivity and high diastereoselectivities.

A convergent and highly stereocontrolled total synthesis of Elisabethin is accomplished. The Elisabethane carbon skeleton is assembled via intramolecular Diels-Alder (IMDA) cyclization.

Research has been conducted on Lewis acid-mediated Diels-Alder reactions of quinol lactones. Results demonstrate that these reactions produce regioselectivity which is opposite uncatalyzed reaction.

The Diels-Alder method is one of the most important methods based exclusively on organic catalysts in synthetic chemistry involving enantioselective processes. Other methods used in synthetic chemistry to study such unique phenomena are discussed and a highly diasteroselective strategy for metal free Diels-Alder reactions is documented.

The dihapto coordination of benzene by the pi-basic metal fragment {[TpRe(CO)(MeIm)} effectively dearomatizes benzene. The oxidation of the rhenium metal center promotes decomplexation, providing access to the bicyclo[2.2.2]-octadiene.

Results show that addition of the vinylanisole cation radical to cyclopentadiene and trans-anethole are stepwise reactions. Data demonstrate a stepwise cation radical Diels-Alder cycloadditions and reactions involving the cis,trans isomers of 1,2-diaryloxyethenes and 1,3-cyclopentadiene.

A study was conducted to assess the viability of a method which utilizes a highly convergent synthesis of octahydroindole derivatives. The method, which can be applied toward the core skeleton of the dendrobium, lycorane, and strychnos alkaloid ring systems, is based upon an intramolecular Diels-Alder reaction of 2-aminofurans. Further research is being undertaken as to the application of the method toward the construction of more complex alkaloids containing octahydroindole skeleton.