Enantiopure, monodisperse alleno-acetylenic oligomers and cyclooligomers

Tert-butyl-substituted diethynylallenes (DEAs) are ideal for the construction of novel topologies because undesirable reactions on the cumulenic moiety are suppressed. The authors developed the asym. synthesis of two shape-persistent enantiopure alleno-acetylenic macrocycles. The solid-state structures of these two chiral macrocycles (D4 and C2 sym.) were detd. by single-crystal X-Ray diffraction. Optical and chiroptical properties were also analyzed on the basis of time-dependent quantum chem. calcns.