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Two principal approaches to create a new type of catalysis and high catalytic efficiency are explained. The importance of the molecular design of acid-base catalysts for the asymmetric direct aldol reaction s illustrated.

Various alpha, beta-unsaturated carbonyl compounds were coordinated aluminum tris(1,6-diphenylphenoxide) (ATPH) to give the corresponding Lewis acid-base complexes in distinctive coordinate fashion. ATPH recognizes carbonyl substrates and subsequently orients itself as it forms a stable complex through selective coordination with the carbonyl oxygen.

Catalytic asymmetric Hetero diels-Alder reactions are developed using chiral zirconium catalysts. These reactions are successfully applied to concise syntheses of biologically important natural pyranone derivatives (+)-Prelactone C and (+)-9-deoxygoniopypyrone.

Asymmetric Lewis acid-catalyzed Diels-Alder reaction of chiral, unsymmetrical maleates yields optically-active, unsymmetrical cis-cyclohexane-1,2-dicarboxylate derivatives. The high diastereoselectivity of the reaction indicates an attractive pi-pi interaction between the maleate C double bond C and the phenyl groups of chiral supplements such as alpha-phenethyl and trans-2-phenylcyclohexyl groups.

The structural dynamics hidden behind a series of aminoorganoboron (AOB) compounds that has involved a recombinant of covalent, dative, and hydrogen bonds is described. The structural dynamics favoring an open structure is important for catalysis, as represented by methanolysis of activated amides.

The chiral calcium species prepared from calcium isopropoxide and chiral bisoxazoline ligands were used to develop the catalytic asymmetric 1,4-addition and [3+2] cycloaddition reactions. The findings revealed that the reaction produced to several kinds of optically active substituted pyrrolidine derivatives such as 3-substituted glutamic acid containing contiguous stereogenic tertiary and quaternary carbon centers with high diastereo- and enantioselectivities.

The first highly anti-selective direct-type catalytic aldol reactions of amides with aldehydes are disclosed. It is observed that aldol reactions are among the most powerful and efficient methods for carbon-carbon bond formation and continuous efforts are dedicated to the development of catalytic asymmetric aldol reactions.

The asymmetric coupling of various phenol or aniline derivatives with bulky aryllead triacetates is examined by using optically active amines, strychnine and brucine. Results suggested the effectiveness of lithiation in phenol coupling and magnesation of anilines is critical for aniline coupling.

A novel Ca-Box catalysts are developed from calcium alkoxides and methylene bridges Box ligands, which have promoted two types of catalytic asymmetric additions of [alpha]-amino acid derivatives with [alpha],[beta]-unsaturated carbonyl compounds. The reaction does not require excess amounts of electrophiles or the external addition of bases in contrast to usual methods such as these using phase-transfer catalysts.

Nucleophilic dearomatic functionalization is discussed.

The first example of the diastereo- and enantioselective direct coupling of aryllead compounds with phenol derivatives is presented. This represents a new approach to optically active aryl compounds with axial chirality that is applicable even to bulky aromatics. Advantages of this technique include the possibility of bi- or terphenyl construction directly from phenols and the possibility of introducing two aromatic nuclei simultaneously to 3,5-disubstituted phenols, to afford terphenyls with high diastereoselectivity.

A study was conducted on a strategy for combining two different carbonyl compounds using lithium diisopropyl amide (LDA) whereby both the substrates are complexed with the bulky aluminum reagent aluminum tris(2,6-diphenylphenoxide) (ATPH). The results indicate that the proton abstraction and subsequent bond formation should be a fast process. Moreover, the two different carbonyl reactants and ATPH should be combined prior to treatment with LDA to provide effective cross-coupling.

A new technique for the kinetically regulated production of the more-substituted enolate by the combined application of aluminum tris(2,6-diphenylphenoxide) and lithium diisopropylamide (LDA) is presented. A synthetically useful, highly selective alkylation at the more-substituted alpha-carbon of unsymmetrical ketones was accomplished by extending the Lewis acid-base complexation system to the ordinary ketone alkylation method utilizing LDA and electrophilic alkylating agents.

A facile method for the selective 1,4-reduction of alpha,beta-unsaturated carbonyl compounds involves complexation with aluminum tris(2,6-diphenylphenoxide) (ATPH) coupled with the reducing action of diisobutylaluminum hydride-butyllithium (DIBAL-n-BuLi). The procedure favors the reduction of a single bond in the double-bonded, doubly conjugated ketone and gives alpha-methylated ketone in excellent yield. Good yields of aldehydes are also achieved from the reduction of alpha,beta-unsaturated aldehydes.

A new synthetic procedure enables the design of an optically pure Lewis acid (R)-ATBN, a chiral aluminum tris(2, 6-diphenylphenoxide) analogue. (R)-ATBN is an efficient reagent for asymmetric Claisen rearrangement of allyl vinyl ethers, producing 61% ee. Change of Lewis acid from (R)-ATBN to (R)-ATBN-F increases the enantio-selectivity to 86%. X-ray and NMR experiments help determine the structure of (R)-ATBN. A suggested mechanism helps explain the enantioselectivity observed with (R)-ATBN-F.

The preliminary results on the investigation on chemoselective functionalization of sterically more hindered aldehyde carbonyl group is discussed. Certain modified organoaluminum reagents featuring Lewis acidic molecular cleft for recognition and stabilization of structurally similar aldehydes are used to achieve opposite selectivity. Excellent chemoselective alkylation is observed between aldehydes and ketones.

Examines the conjugate reduction of alpha,BETA-unsaturated carbonyl compounds by complexation with aluminum tris(2,6-diphenylphenoxide). Study methodologies; What affects the chemoselectivity and yield of alpha,BETA-unsaturated carbonyl compounds; Reaction of enolate/ATPH complex with TfOH; Findings revealed that the reduction of alpha,BETA-unsaturated aldehydes with aluminum hydrides gives unsaturated and/or saturated primary alcohols; Concluding remarks.