These are preliminary reports that have not been peer-reviewed. They should not be regarded as conclusive, guide clinical practice/health-related behavior, or be reported in news media as established information. For more information, please see our FAQs.
2 files

On the Conrotatory Ring Opening of 3-Carbomethoxycyclobutene Vis-À-Vis 3-Carbomethoxy-1,2-Benzocyclobutene and the Predominant Inward Opening of 3-Dimethylaminocarbonyl-1,2-Benzocyclobutene

submitted on 17.09.2018, 13:52 and posted on 18.09.2018, 15:38 by Veejendra Yadav, Dasari L V K Prasad, Arpita Yadav, Maddali L N Rao

The torquoselectivity of conrotatory ring opening of 3-carbomethoxycyclobutene is controlled by pC1C2→s*C3C4 and sC3C4→p*CO interactions in the transition state in a 4-electron process as opposed to only sC3C4→p*CO interaction in an apparently 8-electron event in 3-carbomethoxy-1,2-benzocyclobutene. The ring opening of 3-carbomethoxy-1,2-benzocyclobutene is sufficiently endothermic. We therefore argue that the reverse ring closing reaction is faster than the forward ring opening reaction and, thus, it establishes an equilibrium between the two and subsequently allows formation of the more stable species via outward ring opening reaction. Application of this argument to 3-dimethylaminocarbonyl-1,2-benzocyclobutene explains the predominantly observed inward opening.


Email Address of Submitting Author


Indian Institute of Technology Kanpur



ORCID For Submitting Author


Declaration of Conflict of Interest

The authors declare no competing financial interest.