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Iridium-catalyzed asymmetric allylic alkylation of monoaryl substrates with chiral phosphites was investigated. Results indicate that the choice of solvent is very important to improve the yield of ee in the transition metacatalyzed reactions.

Research has been conducted on the homooxacalix[3]arenes. The introduction of different functional groups on the upper rim of these homooxacalix[3]arenes and the functions of the chromogenic nitrohomooxacalix[3]arene have been investigated and the details are reported.

Research has been conducted on the tetraoxacalix[3]arenes. The synthesis of the new skeleton of these arenes, their X-ray crystal structure and binding studies toward alkali metal cations are discussed.

Research was conducted to examine the first stepwise synthesis of some hexahomooxacalix(3)arenes bearing various substituents on their upper rim using acid-catalyzed cyclization. An X-ray crystallographic analysis of the hexahomooxacalix(3)arene derivatives revealed two conformations which indicated that they adopt a cone conformation due to three intramolecular hydrogen bondings in the solid state.

The diastereoselective alkylation of a binaphthyl ester obtained from (S)-naphthyl phenylacetate, using LDA as a base in THF produces an S,S-isomer as the major product. The increase in the diastereomeric excess by using n-BuLi, is due to the complex-induced proximity effect during enolate formation. During enolate formation, the (E)-enolate is the major product from phenyl phenylacetate. The treatment of organometallics to binaphthyl ester results in the formation of respective optically active ketones.

Chiral allyl- and crotyphosphonate reagents were used in an asymmetric conjugate addition reactions. The anions of these reagents were reacted with alpha,beta-unsaturated cyclic ketones. Reactions occurred at the gamma-positions of the reagents, indicating efficient enantiotopic face discrimination caused by remote asymmetric induction. Trans alpha,beta-dialkylated products were formed from tandem vicinal dialkylation based on Michael addition-enolate methylation.

The chiral 1-(alkylsulfinyl)-2-nitroalkenes, whose preparation involved diastereoselective cycloadditions of trisubstituted dienophiles with cyclopentadiene in the presence of Lewis acids, was developed as dienophiles for assymetric Diels-Alder reactions. E-dienophiles revealed a lower diastereo- and endo/exo-selectivity than did the Z-sulfinyldienophiles.

The asymmetric synthesis of optically active oligonapthalenes through three different pathways, which depend on the variations of the naphthalene side chains, is reported. The chains on the naphthalene have played vital roles for chirality induction and they are the only method for constructing oligonaphthalenes where all-axial chirality, the types and the alignments of the functional groups on the side chains are controlled.

The helical structures attract considerable attention, and various artificial helical molecules are synthesized, in the field of supramolecular chemistry. The helical structure is one of the most ordered structures and packs molecular information's into a restricted space.

Research was conducted to examine the visualization of molecular length of alpha,omega-diamines and temperature by a receptor based on phenolphthalein and crown ether. Experiments reveal that the terminal diamine (n = 9) dissociates from the host molecule to show free rotation at a higher temperature. To better understand the phenomena that color development due to complex formation reflects changes in temperature, the structure of the colored complex was examined in detail. Results show that phenolphthalein is an interesting molecule that makes it possible to visualize molecular length.

Nuclear magnetic resonance spectroscopy was done to evaluate the activity of a newly developed nucleophilic catalyst. The new catalyst which was designed based on the theory of attractive interaction in nonorganometallic species, was found to promote the kinetic resolution of racemic alcohols via enantioselective acylation at ambient temperature. Further studies are needed to confirm the assumption that the new catalyst can also enhance several other types of asymmetric reactions.

Carbamates are the chiral proton sources obtained from 1,1'-binaphthalene-8,8'- diol, and they can protonate the magnesium enolate of 2-alkyltetralones with high enantiomeric excess. A high degree of enantiomeric protonation is observed when the counter cation of the enolate is altered. The acidic hydrogen in the chiral proton sources is located in a highly chiral microenvironment.

A new method facilitates the asymmetric alpha-alkylation of optically active N-methyl-N-Boc-phenylalanine derivatives without the use of any external chiral source. Asymmetric alpha-alkylation of N-Boc-phenylalanine with different bases suggests lithium 2,2,6,6-tetramethylpiperidide to be the efficient base for asymmetric induction. A mechanistic study suggests a configurationally stable carbanion as the possible intermediate.

The oxidative homocoupling of optically active binaphthalenes 1a-d with a stoichiometric amount of CuCl2 and amines afforded quaternaphthalenes 2a-d in up to 93% de. The high diastereoselectivities were achieved through three different pathways (epimerization of the axis together with diastereoselective crystallization, thermodynamic, and kinetic control pathways). The type of side chains on the naphthalene influenced which pathway dominates. Three pathways were applicable to octinaphthalenes (8a-d) and hexadecanaphthalene 10a with 46–99% de. The absolute configuration of the newly formed axial bond was determined by (1) X-ray crystallographic analysis, (2) transformation to known compounds 15 and 16, (3) CD spectra of oligonaphthalenes with two pyrene rings as exciton parts, and (4) the shift values in 13C NMR spectra of 13C-enriched derivatives 29–31 toward chiral shift reagent Eu(+tfc)3. [ABSTRACT FROM AUTHOR]