Kinetic Control in the Synthesis of a Möbius Tris((ethynyl)[5]helicene) Macrocycle Using Alkyne Metathesis
Submitted by Jun Zhu on Mon, 03/30/2020 - 09:39The synthesis of conjugated Möbius molecules remains elusive since twisted and macrocyclic structures are low entropy species sporting their own synthetic challenges. Here we report the synthesis of a Möbius macrocycle in 84% yield from the alkyne metathesis of 2,13-bispropynyl[5]helicene. MALDI-MS, NMR, and X-ray diffraction indicated a trimeric product of two-fold symmetry with PPM/MMP configurations in the helicene subunits.