6533b7d2fe1ef96bd125e91d

RESEARCH PRODUCT

ChemInform Abstract: Two Strained Hexahelicenophanes.

Dieter SchollmeyerHerbert MeierManfred Schwertel

subject

Steric effectschemistry.chemical_compoundCrystallographyHelicenechemistryGeneral MedicineCrystal structureGround stateRing (chemistry)BenzeneRacemization

description

The crystal structures of the [6]­helicenes 4,13-(1,10-deca­methyl­ene­dioxy)­hexahelicene, C36H34O2, (I), and 4,13-(1,8-octa­methyl­ene­dioxy)­hexahelicene, C34H30O2, (II), show strong steric interactions between the terminal benzene rings and the poly­methyl­ene­dioxy chains. The shortest ring A and F distances amount to 2.941 (3) and 2.902 (3) A, respectively. The increased steric energy of the ground state is responsible for a significantly lower racemization barrier of (I) and (II) in comparison to the unsubstituted [6]­helicene.

yearjournalcountryeditionlanguage
2000-09-19ChemInform
https://doi.org/10.1002/chin.200038023