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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.

Dichlorodiethoxysilane was treated with isoprene in the presence of magnesium in THF. It was found that new silacyclopentene derivatives i.e., 1,1-diethoxy-3-methyl-1-silacyclopentene-3(1), and 2,7-dimethyl-5-silaspiro[4.4]nonadiene-2,7(2), were produced in good yields, while sodium was used instead of magnesium in the reaction 2was obtained in a low yield.

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.

Application of optically active carbonfunctional organosilanes for the determination agent of optical purities of chiral amines, alcohols, and carboxylic acids by using NMR spectrometer were investigated.