Endohedral Hydrogen Bonding Templates the Formation of a Highly Strained Covalent Organic Cage Compound*.

ABSTRACT: A highly strained covalent organic cage compound was synthesized from hexahydroxy tribenzotriquinacene (TBTQ) and a meta-terphenyl-based diboronic acid with an additional benzoic acid substituent in 2'-position. Usually, a 120° bite angle in the unsubstituted ditopic linker favors the formation of a [4+6] cage assembly. Here, the introduction of the benzoic acid group is shown to lead to a perfectly preorganized circular hydrogen-bonding array in the cavity of a trigonal-bipyramidal [2+3] cage, which energetically overcompensates the additional strain energy caused by the larger mismatch in bite angles for the smaller assembly. The strained cage compound was analyzed by mass spectrometry and ¹ H, ¹³ C and DOSY NMR spectroscopy. DFT calculations revealed the energetic

SUBMITTER: Schafer N 

PROVIDER: S-EPMC8048910 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature