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As a basic model reaction for assembling specific functional carbohydrate molecules on a novel core substance by making covalent bonds, an efficient one-pot reaction involving Birch reduction and a subsequent SN2 replacement was developed, employing trivalent and tetravalent carbosilane bromides as the core and monodeoxy-monomercapto-ß-cyclodextrin as the functional carbohydrate. It was confirmed that carbosilane derivatives containing a suitable spacer molecule were of wide applicability as a new core substance for the construction of diverse functional materials.

Optically active α-amino organosilanes such as benzylmethyl(o- or p-tolyl)silylmethylamine were converted into benzylmethylphenyl(o- or p-tolyl)silane, of which the configurations had been known. From these observations, it was found that (+)- and (−)-benzylmethyl(o- or p-tolyl)silylmethylamine has Sand Rconfiguration respectively. Furthermore, the stereochemistry of the reaction of benzylmethyl(methoxy)phenylsilane with some organometallic agents was investigated.

A facile cleavage reaction of the germanium–carbon bond of (germylmethyl)amine derivatives to give a germyl anion and an azomethine derivative was developed. The effects of substituents such as phenyl, benzyl, and ethyl groups on the germanium and nitrogen atoms of the (germylmethyl)amine derivatives on the cleavage reaction, were investigated. The mechanism was also investigated based on the stereochemistry of the cleavage reaction using an optically active organogermanium compound.

Reduction of the 7-silanorbornene derivatives obtained from Diels–Alder reactions of 1,1,3,4-tetramethylsilacyclopenta-2,4-diene (1a), and 2,3-dimethyl-5-silaspiro[4.4]nona-1,3-diene (1b) with maleic anhydride was carried out by lithium aluminum hydride (LAH) to give diol derivatives. Attempts to substitute the hydroxyl groups with chlorine using various chlorination agents such as thionyl chloride and triphenylphosphine in carbon tetrachloride were unsuccessful. The latter reaction, however, gave a corresponding ether derivative as a result of intramolecular cyclization. Reactions of the 7-silanorbornene derivatives with some nucleophiles such as LAH, (n-Bu)4NF, n-BuLi, and PhLi were also investigated.

The in situreaction of dialkoxydichlorosilanes, such as dimethoxy-, diethoxy-, dipropoxy-, dibutoxy-, and diisobutoxydichlorosilane, with isoprene and magnesium in tetrahydrofuran (THF) was investigated. It was found that the double annelation product, i.e., 2,7-dimethyl-5-silaspiro[4.4]nona-2,7-diene (1), was obtained from diethoxy-, dipropoxy-, and dibutoxydichlorosilane in 87.0, 65.2, and 66.5% yields respectively. On the other hand, the reaction of dimethoxy- and diethoxydichlorosilane with butadiene and magnesium in THF gave 5-silaspiro[4.4]nona-2,7-diene (7) in 20.7 and 35.4% yields respectively. Several silaspirononane derivatives were synthesized from 1.

New optically active a-amino organosilanes, such as benzylmethylphenylsilylmethylamine, benzylmethyltolylsilylmethylamines, and anisylbenzylmethylsilylmethylamines, were obtained by the fractional crystallization of the salts of the amines and (+)-tartaric acid. Benzylmethylphenylsilylmethylamine was converted into benzylmethyl-1-naphthylphenylsilane, of which the configuration had been known. From these observations, it was found that benzylmethylphenylsilylmethylamine, benzylmethylphenylsilane, and benzylmethoxymethylphenylsilane had S(+), S(-), and S(+) configurations respectively.

New optically active organosilicon compounds such as (benzylmethylphenylsilyl)acetic acid (1) and (ethylmethylphenylsilyl)acetic acid (2) were synthesized. Application of these acids as the optical purity determining agents for chiral amines and alcohols were successfully carried out. In addition, it was also revealed that optically active (benzylmethylphenylsilyl)methylamine (3) and [benzylmethyl(o-tolyl)silyl]methylamine (4) are able to be used as the optical purity determining agents for chiral carboxylic acids.

The polymerization of 1,1,3-trimethyl-1-silacyclopentene-3 (I), 1-methyl-, 1-allyl-1,1-diallyl-1-silacyclopentenes and -pentanes with aluminum chloride was carried out. By means of an IR spectroscopic analysis of the resulting polymers, it was established that not only ring opening but also vinyl polymerization due to the C–C double bond occur in this polymerization. Attempts to polymerize I with other catalysts, such as BF3·OEt2, AIBN, KOH, and a Ziegler catalyst, were unsuccessful.

Reaction of silole derivatives such as 1,1,3,4-tetramethylsilole (1)1)and 2,3-dimethyl-5-silaspiro[4.4]nona-1,3-diene (2) with dimethyl acetylenedicarboxylate (DMADC) were investigated. It was found that the reactions of 1and 2with DMADC in toluene gave 7-membered ring compounds; trimethyl 7-methoxy-3,3,3′,4′-tetramethyl-6-oxa-3-sila-1,2-benzocyclohepta-1,4-diene-4,5,6′-tricarboxylate and trimethyl 5-methoxy- 8,9-dimethylspiro[5H-4,1-benzoxasilepin-1,1′-silacyclopentane]-2,3,6-tricarboxylate, respectively.

New optically active organogermanium compounds, such as [methylphenyl(o-tolyl)-, benzylmethylphenyl-, benzylmethyl(o-tolyl)-, and benzyl(o-methoxyphenyl)methylgermyl]methylamine, were prepared in high optical purity.

(±)-a-Ethylbenzylamine ((±)-1) was efficiently resolved into a pair of enantiomers by fractional crystallization as its cis-2-benzamidocyclohexanecarboxylic acid (2) salt. Moreover, it was found that each of both enantiomers was obtained by mutual resolution between (±)-1and (±)-2. The optically active amine (1) was substantially capable of resolving a variety of chiral carboxylic acids.