Borazine

The compound was reported in 1926 by the chemists Alfred Stock and Erich Pohland by a reaction of diborane with ammonia.

An alternative more efficient route begins with sodium borohydride and ammonium sulfate:[4] In a two-step process to borazine, boron trichloride is first converted to trichloroborazine: The B-Cl bonds are subsequently converted to B-H bonds: Borazine is isoelectronic with benzene and has similar connectivity, so it is sometimes referred to as "inorganic benzene".

X-ray crystallographic structural determinations show that the bond lengths within the borazine ring are all equivalent at 1.429 Å, a property shared by benzene.

The number of pi electrons in borazine obeys the 4n + 2 rule, and the B-N bond lengths are equal, which suggests the compound may be aromatic.

The electronegativity difference between boron and nitrogen, however, creates an unequal sharing of charge which results in bonds with greater ionic character, and thus it is expected to have poorer delocalization of electrons than the all-carbon analog.

[6] In the NBO model, B-N bonds in the ring are slightly displaced from the nuclear axes, and B and N have large differences in charge.

Borazine can also be used as a precursor to grow hexagonal boron nitride (h-BN) thin films and single layers on catalytic surfaces such as copper,[9] platinum,[10] nickel[11] iron[12] and many more, with chemical vapor deposition (CVD).

[13] Among other B-N type compounds mixed amino-nitro substituted borazines have been predicted to outperform carbon based explosives such as CL-20.

NFPA 704 four-colored diamond Health 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroform Flammability 2: Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur. Flash point between 38 and 93 °C (100 and 200 °F). E.g. diesel fuel Instability 1: Normally stable, but can become unstable at elevated temperatures and pressures. E.g. calcium Special hazards (white): no code
Polyborazylene
synthetic route to boron carbonitrides, first step a hydroboration reaction to an oligomeric precursor followed by step two: pyrolysis
synthetic route to boron carbonitrides, first step a hydroboration reaction to an oligomeric precursor followed by step two: pyrolysis