• Source: 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]−.




Adducts


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:

C5H5N + MeOBC5H5SiMe3 → C5H5N-BC5H5 + MeOSiMe3
The pyridine adduct C5H5N-BC5H5 is structurally related to biphenyl. 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.

The borabenzene-pyridine adduct behaves like a diene, not an analog of biphenyl, and will undergo Diels-Alder reactions.




See also


6-membered aromatic rings with one carbon replaced by another group: silabenzene, germabenzene, stannabenzene, pyridine, phosphorine, arsabenzene, stibabenzene, bismabenzene, pyrylium, thiopyrylium, selenopyrylium, telluropyrylium
Borazine




References

Kata Kunci Pencarian:

• Borabenzene
• Boratabenzene
• Benzene
• Organoboron chemistry
• Thiopyran
• Phosphorine
• Aromaticity
• Cyclic compound
• Boraacenes
• Pyridine