Divergent Synthesis of Double Heterohelicenes as Strong Chiral Double Hydrogen-Bonding Donors

Org Lett. 2022 Sep 16;24(36):6670-6675. doi: 10.1021/acs.orglett.2c02734. Epub 2022 Sep 2.

Abstract

We developed a very efficient and expandable divergent approach initiated by a direct electrophilic borylation at phenyl rings to synthesize a series of double heterohelicenes. Their π-extended structures with pristine zigzag nitrogen (N)-boron (B)-nitrogen (N) edges offer them substantial physical properties and strong double hydrogen-bond donating capability. The isolated (P,P) and (M,M) enantiomers exhibit circularly polarized luminescence in response to hydrogen-bonding interactions.