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Chiral separation by elution chromatography (EC) with chiral stationary phases (CSPs) is useful for the quick preparation of enantiomers in the developing stage of new drugs. The use of this method is limited to a small separation, less than kilo-gram scale, because of the large solvent consumption. The simulated moving bed (SMB) process is good to separate two components, and it has been developed for the application to chiral separations. As compared to the EC system in our study, the productivity of the SMB process is twenty times better, and the solvent consumption is less than one twentieth. This shows the good possibility that the SMB technology can be applied to the industrial-scale production to supply enantiomers. With improvement of the process, the range of production will be spread from hundred grams to several ten tons.

The importance of optically active compounds for pharmaceutical usages has increased. High-performance liquid chromatographic (HPLC) resolution on chiral stationary phases (CSPs) is useful for the analysis of the compounds as well the sample preparations to estimate in the developing stages. CSPs consisting of polysaccharide derviatives were developed by adsorbing them on silica gel on the basis of information obtained from cellulose triacetate. The characteristics of cellulosic esters (OA, OB, OJ, OK) and carbamtes (OC, OF, OG, OD), and amylosic carbamtes (AS, AD) in chiral recognition were introduced with many examples. The optimization of sepqrating conditions are discussed in mentioning the differences among the acidic, neutral or basic compounds. Furthermore, we introduced the principle and applications on the Simulated Moving Bed process to produce optically active compounds in the industrial scale as one of the HPLC methods.

Chiral separation by elution chromatography (EC) with chiral stationary phases (CSPs) is useful for the quick preparation of enantiomers in the developing stage of new drugs. The use of this method is limited to a small separation, less than kilo-gram scale, because of the large solvent consumption. The simulated moving bed (SMB) process is good to separate two components, and it has been developed for the application to chiral separations. As compared to the EC system in our study, the productivity of the SMB process is twenty times better, and the solvent consumption is less than one twentieth. This shows the good possibility that the SMB technology can be applied to the industrial-scale production to supply enantiomers. With improvement of the process, the range of production will be spread from hundred grams to several ten tons.

The reaction of cycloalkenes(cyclopentene, cyclohexene, cycloheptene, cyclooctene, 1-methylcyclohexene, and norbornene) with Et 2 MeSiH and carbon monoxide in the presence of Co 2 (CO) 8 gave the corresponding diethylmethylsiloxymethylenecycloalkenes. In such reactions of cyclohexene, the following hydrosilanes gave the corresponding siloxymethylenecyclohexanes: Me 3 SiH, EtMe 2 SiH, Et 2 MeSiH, Et 3 SiH, PhMe 2 SiH, Ph 2 MeSiH. Effects of the reaction conditions(the pressure of carbon monoxide, the temperature, and the molar ratio of cyclohexene to Et 2 MeSiH) were examined. The yield of diethylmethylsiloxymethylenecyclohexane increased remarkably with increasing molar ratio of cyclohexene to Et 2 MeSiH. At higher temperature, the yield of the isomerization product, 1-(diethylmethylsiloxymethyl)-cyclohex-1-ene, increased.