Borabenzene
Borabenzene is a hypothetical organoboron compound with the formula C5H5B. Unlike the related but highly stable benzene molecule, borabenzene would be electron-deficient. Related derivatives are the boratabenzene anions, including the parent [C5H5BH]−.
AdductsEdit
Adducts of borabenzene with Lewis bases are isolatable. Since borabenzene is unavailable, these adducts require indirect methods. 4-Silyl-1-methoxyboracyclohexadiene is used as a precursor to the borabenzene:
- Template:Chem + Template:Chem → Template:Chem + MeOSiMe3
The pyridine adduct Template:Chem is structurally related to biphenyl.<ref>Template:Cite journal</ref> It is a yellow whereas biphenyl is colorless, indicating distinct electronic structures. The pyridine ligand is tightly bound: no exchange is observed with free pyridine, even at elevated temperatures.
- Template:Clear-leftFile:Borabenzene adducts.pngAdducts of borabenzene with pyridine and triphenylphosphine.
The borabenzene-pyridine adduct behaves like a diene, not an analog of biphenyl, and will undergo Diels-Alder reactions.<ref>Template:Cite journal</ref>
See alsoEdit
- 6-membered aromatic rings with one carbon replaced by another group: silabenzene, germabenzene, stannabenzene, pyridine, phosphorine, arsabenzene, stibabenzene, bismabenzene, pyrylium, thiopyrylium, selenopyrylium, telluropyrylium
- Borazine
ReferencesEdit
<references/>Template:Boron heterocycles