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A novel type of molecularly imprinted polymer (MIP), N-benzoyl-(S)-valine anilide-imprinted polymer (IP-2), was prepared using hydrogen-bonding interactions as a main force in the pre-polymerization step. The performance of the IP-2 was evaluated via batch procedure and compared with a (S)-valine anilide-imprinted polymer (IP-1) that was prepared using an ionic interaction that is stronger than hydrogen bonding. Although both polymers showed a preferential adsorbability for (S)-amino acid derivatives, different performances were observed in terms of adsorbability and enantioselectivity. In addition, the IP-2 was able to recognize the enantiomer of a valine-derived chiral catalyst. This phenomenon was applied to a chiral amplification reaction, and a highly selective asymmetric Mannich-type amination was achieved using the combination of a racemic catalyst and a MIP.

We evaluated the adsorbability and selectivity of (S)-valine anilide imprinted molecularly imprinted polymer (MIP) using a batch procedure that is both independent and precise. This study revealed important information about the relationship between the performance of MIPs and experimental factors such as the components of MIP synthesis and a reaction solvent. Herein, we also describe the problems associated with the preparation of a "non-imprinted polymer," which is often used to evaluate the effect of a template molecule, and we propose a new type of reference polymer, "blank polymer."

The preparation of a new class of "roofed" β-iminodisulfides from sterically congested, conformationally rigid chiral 2-thiazolidinones is described. A functional survey of palladium-catalyzed asymmetric allylic alkylation of 1,3-diphenyl-2-propenyl acetate with dimethyl malonate proved that symmetrical "roofed" β-iminodisulfides are efficient chiral ligands, showing enantioselectivity opposite that associated with chiral "roofed" β-iminothioether ligands.

The thermal reaction of 3-[(1S)-2-alkoxyl-1-apocamphanecarbonyl]-2-oxazolones with dialkyl azodicarboxylates results in exclusive formation of [4+2] type cycloadducts with moderate levels of diastereofacial selection, which serve as versatile chiral synthons for a wide variety of 4-alkyl and 4-aryl-2-oxazolidinones as well as α-amino acids.

Starting with (1S)-ketopinic acid (7, 7-dimethyl-2-oxo-bicyclo[2.2.1]heptane-1-carboxylic acid), a facile high-yield synthesis of diastereomerically pure (1S, 2R)- and (1S, 2S)-2-hydroxy-7, 7-dimethylbicyclo[2.2.1]heptane-1-carboxylic acids, potentially useful as chiral auxiliaries, has been achieved : the key step for the latter (2-endo isomer) involves the base-catalyzed epimerization of the (1S, 2R)-2-hydoxy isomer (2-exo-isomer), exclusively formed by the L-Selectride[○!R] reduction of alkyl ketopinate, via the retro-aldol reaction.