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Lithium dialkylamides such as lithium diisopropylamide (LDA) are now used widely as bases of choice in synthetic organic chemistry. This article describes a relatively new area of asymmetric synthesis in which chiral lithium amide bases act both as bases and as chiral auxiliaries in the reactions to give optically active products enantioselectively. Examples of enantioselective deprotonation, enantioselective protonation, enantioselective carbon-carbon bond formation, and enantioselective dehydrohalogenation are reviewed. Since generation of carbanions by bases and their reactions constitute the backbone of organic synthesis, the chemistry presented here offers attractive opportunities for further developments.

During the last two decades, the concept of molecular recognition has become to play a central role in chemistry. So-called host-guest chemistry employing crown ethers, cryptands and related hosts has contributed to the development of this concept. This review deals with molecular recognition by these hosts for 1) cations, 2) anions, 3) neutral molecules, and 4) chiral guests. And recent studies on their application to asymmetric synthesis and enzyme modeling are briefly summarized.

Osmium tetroxide is one of the most reliable oxidants for preparing vicinal cis-diols from olefins. In this article are reviewed some aspects of recent progress in diastereoface-selective and enantioface-selective oxidation of olefins with osmium tetroxide. The oxidation mechanism is also discussed.

Heteromacrocycles have been widely employed because of the unique property of forming stable complexes with a variety of molecules. Recently, new compounds have been designed to construct a rigid complex-forming cavity, such as cavitand, spherand, cryptophane, calixarene, and cucurbitril, whose syntheses and complex-forming properties are briefly discussed in this article. Moreover, the recent developments in utilization of crown ether-type heteromacrocycles have revealed the great ability to enhance selectivity in organic and asymmetric sythesis. Biomimetic chemistry are also developed by the use of the heteromacrocycles as enzyme mimics, realizing biomimetic reactions, such as acyl transfer, hydrogen transfer, and peptide synthesis.

Recent progress in the construction of chiral quaternary carbon centers by the method of asymmetric carbon-carbon bond forming reaction is described. The article covers, i) asymmetric sythesis by the use of chiral enamines, ii) asymmetric synthesis based on the strategy of fixing conformation of metalloenamines by chelate formation, iii) asymmetric synthesis based on the strategy of optionally controlling the diastereoface selection by an external ligand, iv) asymmetric alkylation by the use of conformationally rigid heterocycles. Asymmetric total syntheses of alkaloid mesembrine, sesquiterpene ivalin, and neolignan megaphone by the application of these methods are also described.