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101.
Hiroshi Hata Dr. Shigeru Yamaguchi Goro Mori Satomi Nakazono Taisuke Katoh Keishi Takatsu Satoru Hiroto Hiroshi Shinokubo Prof. Dr. Atsuhiro Osuka Prof. Dr. 《化学:亚洲杂志》2007,2(7):849-859
Highly regioselective and efficient borylation of a variety of porphyrins has been achieved by reaction with bis(pinacolato)diboron through C? H bond activation under iridium catalysis on the basis of the synthetic protocol developed by Miyaura, Hartwig, and Smith. A boryl group can be selectively introduced at sterically uncongested positions in the peripheral aryl groups of porphyrin substrates whose peripheral β‐positions are sterically hindered. Curiously, β substituents adjacent to the aryl group to be borylated have unexpectedly large effects on the regioselectivity, because the iridium catalyst can discriminate between subtle steric differences. Chemoselective borylation was also achieved for several functionalized porphyrins. This borylation protocol can be applied to various monomeric and oligomeric functional porphyrins, hence offering an efficient route to elaborate multiporphyrin‐based molecular constructs. 相似文献
102.
The importance of the sodium ion transport in biological systems is well known. Numerous studies have dealt with compounds which affect ion transport across membrane systems. However, the mechanism of ion transport across the membrane is still not clear. Hence it is of interest to investigate the interaction of the sodium ion with biologically active compounds in a system where the complex membrane is absent. Such a method of investigation must be able to detect very weak interactions. Sodium-23 nuclear magnetic resonance fits well into this classification. This technique has been used by others1 and by us2 to investigate electrolyte solutions and biological or model systems. We have been interested in the chemistry of cyclopolymethy-lenetetrazoles for some time.3 These compounds are characterized by their strong stimulating action on the central nervous system and, in 相似文献
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