Kenji Matsuo

Pseudomonas fluorescens lipase-catalyzed asymmetric hydrolysis and transesterification of meso-2,5-bis(acetoxymethyl)- and bis(hydroxymethyl)-3,4-(isopropylidenedioxy)tetrahydrofuran

Abstract Pseudomonas fluorescens lipase (PFL)-catalyzed asymmetric hydrolysis of meso -2,5-bis(acetoxymethyl)-3,4-(isopropylidenedioxy)tetrahydrofuran 3 afforded the optically active monoacetate (−)- 7 of high enantiomeric excess (92% ee) in 94% yield. Transesterification of meso -bis(hydroxymethyl)-3,4-(isopropylidenedioxy)tetrahydrofuran 6 using PFL in vinyl acetate gave the monoacetate (+)- 7 of 69% ee in low yield (15%). The absolute configuration of (−)- 7 was determined to be 2 S ,3 S ,4 R ,5 R , by chemical correlation with d -allose 10 .

Molecular structure and magnetic properties of N,N-bis {4-methoxy-3,5-bis(N-tert-butyl-N-oxyamino)phenyl} aminoxyl. An approach to a stable and high-spin pentaradical

A stable pentaradical, N,N-bis{4-methoxy-3,5-bis(N-tert-butyl-N-oxyamino)phenyl)}aminoxyl, is prepared and its ground state determined to be a sextet (S = 5/2) by SQUID magnetization measurements of the pentaradical diluted in poly(vinyl chloride) matrix.

Effect of anionic surfactant on copper extraction with N-8-quinolyl-p-dodecylbenzenesulfonamide in a hollow fiber membrane extractor

Abstract The effect of an anionic surfactant, sodium dioleylsulfosuccinate, on the extraction rate of copper with N-8-quinolyl-p-dodecylbenzenesulfonami rate of the copper chelate complex with sulfuric acid in a hollow fiber membrane extractor was studied. The extraction and stripping rates were remarkably enhanced by the addition of the anionic surfactant in case they were controlled by the interfacial reaction, i.e. at low pH for extraction and at low hydrogen activity for stripping. It was found that the electrostatic interaction between copper and the anionic surfactant played an important role in the extraction. An extraction mechanism for copper with N-8-quinolyl-p-dodecylbenzenesulfonamide in a hollow fiber membrane extractor in the presence of the anionic surfactant was proposed.