The Chemoselective C–C σ-Bond Activation of the Arene Ring of Biphenylene

18 August 2020, Version 1
This content is a preprint and has not undergone peer review at the time of posting.


The chemoselective cleavage of an arene ring in biphenylene is reported using an aluminium(I) complex. The reaction proceeds with complete integrity of the central 4-membered ring despite this ring containing the weakest C–C σ-bond in the hydrocarbon scaffold. A reaction intermediate derived from the (4+1) cycloaddition of the aluminium(I) complex to the p-system of biphenylene was isolated. Further experiments and DFT calculations suggest that this intermediate is involved in breaking of the C–C σ-bond. Activation strain analysis was used to understand the origins of the remarkable chemoselectivity of this system. Both the symmetry and diffuseness of the frontier molecular orbitals of the aluminium(I) fragment are implicated in its unusual reactivity with biphenylene.


C–C activation

Supplementary materials

Biphenylene SI 17thAug


Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.