Takatoshi Yoshida

Synthesis of some 5H-benzo[a]phenoxazin-5-one derivatives

The substituted 6-bromo and 6-chloro-5H-benzo[a]phenoxazin-5-ones, prepared by condensation of substituted 2-aminophenols with 2,3-dibromo or 2,3-dichloro-1,4-naphthoquinone in methanolic potassium hydroxide solution, have been dehalogenated to substituted 5H-benzo[a]phenoxazin-5-ones in the presence of sodium hydrosulfite dissolved in aqueous pyridine under nitrogen atmosphere.

Mechanism of decomposition of α,α-dimethylbenzyl hydroperoxide producing acetophenone and α,α-dimethylbenzyl alcohol in a constant proportion of 2 to 1

In the decomposition of α,α-dimethylbenzyl hydroperoxide (1) by use of copper(II) chlorocomplexes, the novel fact was found that the product ratio of acetophenone (2) to α,α-dimethylbenzyl alcohol (3) is 2 to 1. The kinetics of this result was investigated and a mechanism consistent with the experimental result is proposed.ZusammenfassungBei der Zersetzung von α,α-Dimethylbenzylhydroperoxid (1) unter Verwendung eines Kupfer(II)chlorkomplexes wurde die neue Feststellung gemacht, daß das Produktverhältnis Acetophenon (2): α,α-Dimethylbenzylalkohol (3) stets 2:1 ist. Die Kinetik der Reaktion wurde untersucht und ein Mechanismus vorgeschlagen, der mit dem experimentellen Resultat konsistent ist.

Effect of 1,3:2,4-dibenzylidene-D-sorbitol (DBS) additive on reverse osmosis properties of cellulose acetate membrane

Abstract The performance of the modified membranes prepared by adding aprotic solvent and DBS to Manjikian-named Batch 47-type casting solution was investigated. The addition of 1.5 wt-%, DBS to the casting solution made by mixing cellulose acetate, acetone, formamide, and N,N-dimethylformamide in the proportion of 5:9:2:4 by weight brought about the optimum performance of the resulting membrane. From the results obtained, it is suggested that an addition of proper amount of DBS does not affect the separation mechanism of the cellulose acetate membrane but DBS has the effect of forming a number of homogeneous pores in the membrane surface layer.

Solid Liquid Equilibria with Crystals of Single Component

筆者らは, 単一成分が析出する数種の2成分系および3成分系の凝固点を実測し, 気液平衡で示された方法 (化工, 25, 158 (1961) による3成分系溶液の凝固点の推算値が実測値と大約一致することを示した。