Polyborates oxidation

The general procedure for the preparation of vanadium borates consists in heating a concentrated H2O solution of boric acid and vanadium oxide in an autoclave at 170 °C for several days [143]. Two different vanadium borate clusters 105 and 106 are obtained, one with two polyborate chains coordinated to a contorted vanadium oxide ring (105) and another one with a macrocyclic Bi8036(0H)6 ring (106). The latter ring is composed of six B306(0H) units and has a chair-like conformation (Fig. 27) [143]. 

Polyborate kommen in der Natur vor oder konnen synthetisch im System Metalloxid/Boroxid/Wasser isoliert werden. Die meisten von ihnen sind wasserhaltig, besitzen also die Formel m Metalloxid n Bor-oxid x H20. Man kann aber auch wasserfreie Polyborate durch Schmel-zen oder Erhitzen erhalten. 

Boric acid (H2B8O13), disodium salt, tetrahydrate Boric acid, disodium salt, tetrahydrate Boron sodium oxide, tetrahydrate Caswell No. 406B Disodium octaborate tetrahydrate EPA Pesticide Chemical Code 011103 FLEABOR Polybor 3 Tim-Bor Timber. Fire retardant for treatment of lumber. Registered by EPA as an insecticide, fungicide and herbicide. Borax Consolidated Ltd Environmental Laboratories, Inc. Honolulu Wood Treating Co, Osmose Inc. U.S. Borax. 

The CDT is then hydrogenated and further oxidized at 150°C to cyclododecanol and cyclododecanone with oxygen from the air. In this reaction, up to 5% ketone hydroperoxide occurs, which can be decomposed to form cyclododecanol, cyclododecanone, and dicarboxylic acid. These undesired reactions can be prevented by adding boric acid, which is present as polyboric acid at this temperature. The peroxide probably forms an adduct with the polyboric acid, and the course of this reaction is not yet fully understood. The cyclododecanone is changed to lauryl lactam via the oxime in the usual way (cf. nylon 6). 

Boiling water oxidizes [BH4]" to a mixture containing various polyborate anions, simplified here, while releasing H2 gas ... 

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