Hexaborane, also called hexaborane(10) to distinguish it from hexaborane(12) (B<sub>6</sub>H<sub>12</sub>), is a boron hydride cluster with the formula B<sub>6</sub>H<sub>10</sub>. It is a colorless liquid that is unstable in air.
Hexaborane(10) is classified as a nido-cluster. The boron atoms define a pentagonal pyramid, with four bridging hydrogen atoms and six terminal ones. The point group of the molecule is C<sub>s</sub>.
A laboratory route begins with bromination of pentaborane(11) followed by deprotonation of the bromide to give [BrB<sub>5</sub>H<sub>7</sub>]<sup>âÂÂ</sup>. This anionic cluster is reduced with diborane to give the neutral product:
It can also be generated by pyrolysis of pentaborane(11).
B<sub>6</sub>H<sub>10</sub> can be deprotonated to give [B<sub>6</sub>H<sub>9</sub>]<sup>âÂÂ</sup> or protonated to give [B<sub>6</sub>H<sub>11</sub>]<sup>+</sup>. It can act as a Lewis base towards reactive borane radicals, forming various conjuncto-clusters.