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Among the surface-active compounds containing silicon atoms in the hydrophobic group being widely studied recently, methylsiloxane-oxyalkylene copolymers are reported to have very exellent surface activity. But study on surfactants containing polysilmethylene group has never been reported yet. The authors synthesized such compounds and investigated their physical properties to examine the difference of property between silicon-oxgen bond and silicon-carbon bond and the effect of substitution of carbons in the alkyl chain by silicons.Syntheses were carried out as follow;4, 4, 6, 6-Tetramethyl-4, 6-disilheptanol was prepeard by the reaction of ethylene oxide with the Grignard reagent of 4, 4, 6, 6-tetramethyl-4, 6-disilpentyl chloride obtained by the reaction of trimethylsilylmethyl lithium with chloromethyl-dimethylchlorosilane.Ethyleneoxide-adducts of this disilheptanol were obtained by the usual addition reaction with potassium hydroxide catalyst.Surface tension, wetting power, dispersing power on carbon black in benzene and foaming power of the aqueous solution of the adducts were determined, and it was found that some gave low surface tention at 0.1% and 1.0% solution and good foaming power.But dispersing power on carbon black in benzene and wetting ability to polyvinyl chloride were less.These silmethylene-type compounds were inferior to siloxane-type compound in lowering surface tension and wetting power.In conclusion, siloxane bond is more efficient in lowering surface energy than silmethylene bond, and the effect of substitution of only two carbons in the alkyl chain by silicons is not evident.

無機塩類を除去後陽イオン交換樹脂柱を通して酸型にした陰イオン活性剤の約1%溶液を,0.001～0.004ccロ紙につけ,各種展開剤で展開した。また,同じ活性剤を2Nカセイソーダ,6N塩酸,および2N硫酸で処理した後に展開を行なった。スポットの検出には,ピナクリプトールエローの0.1%溶液を噴霧し,3650Åの紫外線下のケイ光を観察する方法を用いた。得られたクロマトグラムのスポットの位置や有無より,陰イオン活性剤の種類が推定でき,活性剤混合物の分離検出も可能であった。

The rearrangement of (+)-cis- (I) and (−)-trans-pulegone oxide (II) was effected by the catalysis of zinc bromide in boiling benzene to give the same (−)-2,2,5-trimethylcyclohepta-1,3-dione (III), with a retention of the optical activity. The structure of (−)-III with the expanded 7-membered ring was confirmed by the chemical transformation into 1,1,4-trimethyl-cycloheptane(IV), which was identical with that derived from eucarvone(V). Piperitone oxide(VIII) was also converted into diosphenol(X) in the same manner as in pulegone oxides.