Boron nitrogen compounds

Boronic acids readily dehydrate at moderate temperatures (or over P4O10 at room temperature) to give trimeric cyclic anhydrides known as trialkyl(aryl)boroxines  

3 Organic compounds containing boron-oxygen bonds 

Boronic acids RB(0H)2 were first made over a century ago by the unlikely route of slow partial oxidation of the spontaneously flammable trialkyl boranes followed by hydrolysis of the ester so formed (E. Frankland, 1862)  

Many other routes are now available but the most used involve the reaction of Grignard reagents or lithium alkyls on orthoborates or boron trihalides  

Phenylboronic acid in particular has proved invaluable, since its complexes with cis-diols and -polyols have formed the basis 

An ionization mechanism has also been proposed for the scrambling reactions between the adducts of various amines and BCls and BPhCla. Unimolecular ionization of a boron-chlorine bond occurs, and not dissociation of the boron-nitrogen linkage. A similar intermediate to (1), but with bridging methyl groups instead of 

The hydrolyses of cyanoborane adducts with morpholine and with dimethylaniline, R2NHBH2CN + 2H20 + 20H------------------- -R2NH + [B(OH)4r + 2H2 + CN  

Chazov, and L. K. Ivlevi, Khim. Khim. Tekhnol., Trudy Tyumen Ind. Inst. 1972, 257 Ghem. Abs., 1974, 80, 52 710c). 

Many metal borates find important industrial applications (p. 140) and annual world production exceeds 2.9 million tonnes Turkey 1.2, USA 1.1, Argentina 0.26, the former Soviet Union 0.18, Chile 0.13Mt. Main uses are in glass-fibre and cellular insulation, the manufacture of borosilicate glasses and enamels, and as fire retardants. Sodium perborate (for detergents) is manufactured on a 550 000 tonne pa scale. 

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A new class of boron—nitrogen compounds was reported in 1975 when the first iminoborane having two-coordinate boron,... 

Borazine, B3N3Hft, a compound that has been called inorganic benzene because of its similar hexagonal structure (but with alternating B and N atoms in place of C atoms), is the basis of a large class of boron—nitrogen compounds. Write its Lewis structure and predict the composition of the hybrid orbitals used by each B and N atom. 

K. Niedenzu, J. W. Dawson, Boron-Nitrogen Compounds, Springer-Verlag, New York (1965). 

It is now recognized that iminoboranes are not merely unique intermediates but rather are members of an independent class of stable compounds which has its own chemistry such as the aminoboranes, borazines, or other examples of boron-nitrogen compounds. 

Niedenzu, K., Dawson, J. W. Boron-Nitrogen Compounds. In Anorganische und all-gemeine Chemie in Einzeldarstellungen, Vol. VI. Berlin-Heidelberg-New York Springer 1965. 

Figure 4.2 Proton-hydride (H- -H) distances (A) versus B-H- -H angles (degrees) in the Cambridge Structure Database for 18 x-ray structures of boron nitrogen compounds. The numbers correspond to the CSD file names, which can be found in ref. 7. (Reproduced with permission from ref. 8.)...

There are several materials that form nanotubes including boron-nitrogen compounds. Here we will focus on nanotubes derived from carbon. Carbon nanotubes (CNTs) have... 

UA. Pelter u. K. Smith, Boron-Nitrogen Compounds, in Comprehensive Organic Chemistry, Bd. 3, S. 925-932, Pergamon Press, London 1979. 

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