2005/05/14 by Armando Navarro‐Vázquez, Peter R. Schreiner · 3 citations
Chemistry · #Synthesis and Properties of Aromatic Compounds #Cyclization and Aryne Chemistry #Fullerene Chemistry and Applications
paper · doi:10.1021/ja0507968
openalex publication_date 2005/05/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/26
The conformational space of C(10)H(8) 1,2-didehydro[10]annulenes, along with their unimolecular conversion to isonaphthalenes (cyclic allenes), has been studied computationally using DFT (B3LYP), single-reference [CCSD(T)], and multireference (MCQDPT2) post-HF methods. The introduction of the linear alkynyl moiety releases enough angle strain to make a nearly planar "heart" aromatic form the preferred conformer by more than 6 kcal/mol [CCSD(T)] over a localized C(2) "twist" structure, as opposed to the closely related C(10)H(10) [10]annulene system. Computations also show that electrocyclic ring-opening of isonaphthalenes to the heart C(10)H(8) annulene takes place through a low barrier of 15 kcal/mol, and this should be considered the working mechanism for the reported isomerizations during dehydro Diels-Alder reactions of phenylacetylenes.