Tetrahedrane

In a more general sense, the term tetrahedranes is used to describe a class of molecules and ions with related structure, e.g. white phosphorus.

Maier suggested that bonds in the core are prevented from breaking because this would force the substituents closer together (corset effect) resulting in Van der Waals strain.

[3] Due to its bond strain and stoichiometry, tetranitrotetrahedrane has potential as a high-performance energetic material (explosive).

Though the synthesis appears short and simple, by Maier's own account, it took several years of careful observation and optimization to develop the correct conditions for the challenging reactions to take place.

"[9] Eventually, a more scalable synthesis was conceived, in which the last step was the photolysis of a cyclopropenyl-substituted diazomethane, which affords the desired product through the intermediacy of tetrakis(tert-butyl)cyclobutadiene:[10][11] This approach took advantage of the observation that the tetrahedrane and the cyclobutadiene could be interconverted (uv irradiation in the forward direction, heat in the reverse direction).

Tetrakis(trimethylsilyl)tetrahedrane can be prepared by treatment of the cyclobutadiene precursor with tris(pentafluorophenyl)borane[12] and is far more stable than the tert-butyl analogue.

The tetrahedrane skeleton is made up of banana bonds, and hence the carbon atoms are high in s-orbital character.

The standard silicon–silicon bond is much longer (235 pm) and the cage is again enveloped by a total of 16 trimethylsilyl groups, which confer stability.

[20] In this tetrahedrane the cage is protected by four so-called supersilyl groups in which a silicon atom has 3 tert-butyl substituents.

Ball and stick model of tetrahedrane
Ball and stick model of tetrahedrane
Tetra- tert -butyl-tetrahedrane synthesis 1978
Tetra- tert -butyl-tetrahedrane synthesis 1991
Tetrakis(trimethylsilyl)tetrahedrane is relatively stable
Synthesis of tetrakis(trimethylsilyl)tetrahedrane and its dimer.
Tetrasilatetrahedrane
Silicon cluster compound
Structure of [InC(tms) 3 ] 4 , a tetrahedrane with an In 4 core (dark gray = In, orange = Si). [ 21 ]
Metal clusters that have tetrahedral cores are often called tetrahedranes.