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Boron hydride clusters are compounds with the formula B x H y or related anions, where x ≥ 3. Many such cluster compounds are known. Common examples are those with 5, 10, and 12 boron atoms. Although they have few practical applications, the borane hydride clusters exhibit structures and bonding that differs strongly from the patterns seen in ...
A borane is a compound with the formula BR x H y although examples include multi-boron derivatives. A large family of boron hydride clusters is also known. In addition to some applications in organic chemistry , the boranes have attracted much attention as they exhibit structures and bonding that differs strongly from the patterns seen in ...
Borane makes a strong adduct with triethylamine; using this adduct requires harsher conditions in hydroboration. This can be advantageous for cases such as hydroborating trienes to avoid polymerization. More sterically hindered tertiary and silyl amines can deliver borane to alkenes at room temperature. Borane(5) is the dihydrogen complex of
The spectrum of boron monohydride includes a molecular band for the lowest electronic transition X 1 Σ + → A 1 Π with a band head at 433.1 nm (for 0→0) and 437.1 (for 0→1) [3] The spectrum contains P, Q, and R branches. [10] Although BH is a closed shell molecule, it is paramagnetic independent of temperature. [11]
Except a few bulky derivatives, the hydrides (n = 1 or 2) dimerize, like diborane itself. Trisubstituted derivatives, e.g. triethylboron, are monomers. [5] Monoalkyl boranes are relatively rare. When the alkyl group is small, such as methyl, the monoalkylboranes tend to redistribute to give mixtures of diborane and di- and trialkylboranes.
It is soluble in cold water as well as a variety of non-polar and moderately polar solvents. [3] In decaborane, the B 10 framework resembles an incomplete octadecahedron. Each boron has one "radial" hydride, and four boron atoms near the open part of the cluster feature extra hydrides.
A large number of anionic boron hydrides are known, e.g. [B 12 H 12] 2−. The formal oxidation number in boranes is positive, and is based on the assumption that hydrogen is counted as −1 as in active metal hydrides. The mean oxidation number for the boron atoms is then simply the ratio of hydrogen to boron in the molecule.
The great variety of boranes show a huge covalent cluster chemistry, but the heavier group 13 hydrides do not. Despite their formulae, however, they tend to form polymers. Alane(aluminum trihydride) is a strong reducing agent with octahedrally coordinated aluminium atom