Octabetaines: a DFT Study of Unexplored Eight-Membered 10π Heterocycles.

ABSTRACT: Eight-membered 10π heterocyclic mesomeric betaines (HMBs) are unusual in that they are associated with two 1,3-dipolar fragments in mutual conjugation; they are conjugated HMBs belonging to Class 1A. Apart from the characterization of five derivatives of the 1,5-dithia-2,4,6,8-tetrazocine ring in the 1980s, this large family of "aromatic" heterocycles has received no attention. The density functional theory (DFT) study reported here investigates the structure, aromaticity, and bonding of representative examples. The parent structures and aza derivatives are planar, and bond lengths are in agreement with a reported crystal structure. Calculated HOMA aromaticity index values and aromatic stabilization energy (ASE) are consistent with high classical aromaticity. Their magnetic aromaticity, me

SUBMITTER: Ramsden CA 

PROVIDER: S-EPMC11822512 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature