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Two efficient new chiral catalysts were developed for the first highly enantio- and diastereoselective HDA reaction of Brassard type diene with aldehydes. This catalyst system provided one of the most convenient approaches for the construction of 5-methyl-contaiing [delta]-lactone units, which make the methodology more attractive for the synthesis of a variety of natural products.

An efficient enantioselective approach to chiral dihydropyrones is developed by the hetero-Diels-Alder (HDA) reactions of (E)-4-methoxy-2-trimethylsiloxy-penta-1,3-diene with aldehydes and pyruvates. Results reveal that the readily accessible (R)-BINOL-Ti(OiPr)4 (1:1:1) complex is a very effective catalyst for this reaction.

Asymmetric cyanosilylation of aldehydes was achieved by catalysis of 5 mol % of chiral beta-amino alcohol. Results indicate that beta-amino alcohol-Ti(Oi-Pr) (sub 4) complex can efficiently catalyze cyanosilylation of aldehydes, with high ee.

Research has been conducted on the hetero-Diels-Alder reaction of aldehydes with Danishefsky's diene. The role of the chiral Lewis acids in this reaction has been investigated and the results indicate that the effective catalyst for the reaction is Ti(IV)-H (sub)8-BINOL complex.

A new type of [C.sub.2]-symmetric chiral bisguanidine is designed as a very efficient catalyst in the inverse-electron-demand hetero-Diels-Alder reaction of chalcones with azlactones. Hydrogen bonds are vital for the activation and stereoinduction of the reactions and in all cases, the major is HAD adducts, which are obtained as a single diastereomer along with little amount of Michael addition products.

The asymmetric direct vinylogous aldol reaction of unactivated [gamma]-butenolide with aldehydes is developed, which has produced corresponding 5-(1' -hydroxy)butenolide derivatives in high yields and enantioselectivities.

The catalytic enantioselective Roskamp reaction of [alpha]-alkyl-[alpha]-diazoesters with aromatic aldehydes is realized by using a chiral N,N'dioxide-scandium(III) complex. The protocol has provided a good method for preparing chiral [alpha]-alkyl-[beta]-keto esters and 1,3-diols.

The development of an efficient enantioselective Friedel-Crafts alkylation of indoles to ethyl glyoxylate catalyzed by chiral N,N'-dioxide-Sc(III) complex is described. The corresponding 3-indolyl(hydroxy)acetates compounds are produced with high enantioselectivities.

A novel and efficient chiral catalyst system based on N,N'-dioxide-nickel(II) complexes is described for the asymmetric carbonyl-ene reaction. Excellent enantioselectivities are obtained for a broad range of substrates including aromatic, aliphatic glyoxal derivatives, as well as glyoxylate with various alkenes.

Simple amino acids are introduced into the bicyclic bispidine framework for the direct aldol reactions of functionalized ketones to report a novel organocatalyst. The catalyst demonstrated high enantioselectivity for a broad range of substrates.

The article explains the mechanisms involved in the aza-Henry reaction of N-tosyl imines, which are usually catalyzed by N,N'-dioxide-Cu(I) complexes. The reaction is found to give high yields of nitro amines with high enantioselectivities.

A new chiral N,N'-dioxide-Cu catalyst is developed for the asymmetric Henry (nitroaldol) reaction and is used for catalyzing [alpha]-ketoesters. This mechanism has described the origin of reactivity and asymmetric inductivity.

The development of the first enantioselective allylation of [alpha]-ketoesters by chiral using N,N'-dioxide-In(III) complex as catalyst is described.

The asymmetric one-pot, three-component Strecker reaction was observed to produce the [alpha]-amino nitriles in excellent yields with enantioselectivities when [C.sub.2]-symmetric chiral bisformamides was used as catalysis.

A novel chiral indium complex prepared from indium(III) bromide and (S)-pipecolic acid-derived N,N'-dioxides for the enantioselective allylation of ketones is presented.

An efficient multiomponent bifunctional catalyst cyanoformate based on a titanium complex was used for the efficient enantioselective cyanation of aldehydes. The presence of the multicomponent catalyst allowed the enantioselective cyanation reaction to proceed smoothly to afford the desired cyanohydrins ethyl carbonates in moderate to excellent isolated yield with high enantioselectivities.

A highly enantioselective cyanosilylation of ketones promoted by a simple chiral amino acid salt is developed. The reaction is mechanistically interesting as the first chiral organic salt approach, which differed from the known enzyme- and transition metal-based methods.