Oxides boron

Synonyms Boric anhydride boron sesquiox-ide boron trioxide fused boric acid 

In preparation of fluxes component of enamels and glass catalyst in organic reaction 

In 113 workers exposed to boron oxide and boric acid dusts, there were statistically signiflcant increases in symptoms of eye irritation dryness of the mouth, nose, and throat sore throat and productive cough compared with controls. The mean exposure level was 4.1mg/m with a range of 1.2-8.5mg/mk Exposures may occasionally have exceeded 10 mg/mh Because of mixed exposures, the study does not indicate whether boron oxide or boric acid dust is more important in causing symptoms, nor does it indicate the minimum duration of exposure necessary to produce symptoms. 

Excessive absorption of boron oxide may lead to cardiovascular collapse, alterations in temperature regulation, and coma.  

Repeated exposure of rats to an aerosol at a concentration of 470mg/m for 10 weeks caused only mild nasal irritation repeated exposure of rats to 77mg/m for 23 weeks resulted in elevated creatinine and boron content of the urine in addition to increased urinary volume. Conjunctivitis resulted when the dust was applied to the eyes of rabbits, probably the result of the exothermic reaction of boron oxide with water to form boric acid topical application of boron oxide dust to the clipped backs of rabbits produced erythema that persisted for 2-3 days.  

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Allylation with allyl borates takes place smoothly under neutral conditions. Allylic alcohols are also used for allylation in the presence of boron oxide by in situ formation of allylic borates[125]. Similarly, arsenic oxide is used for allylation with allylic aleohols[126]. In addition, it was claimed that the allyl alkyl ethers 201. which are inert by themselves, can be used for the allylation in the presence of boron oxide[127]. 

PORONCOPTPOUNDS - BORON OXIDES, BORIC ACID AND BORATES] pol 4)... 

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