Synfacts 2010(5): 0540-0540  
DOI: 10.1055/s-0029-1219682
Synthesis of Materials and Unnatural Products
© Georg Thieme Verlag Stuttgart ˙ New York

Alleno-Acetylenic Oligomers

Contributor(s): Timothy M. Swager, D. Barney Walker
P. Rivera-Fuentes, J. L. Alonso-Gómez, A. G. Petrovic, F. Santoro, N. Harada, N. Berova, F. Diederich*
ETH Zürich, Switzerland; Columbia University, New York, USA; Consiglio Nazionale delle Ricerche, Pisa, Italy
Further Information

Publication History

Publication Date:
22 April 2010 (online)

Significance

Oligomers comprised of a chiral monomer repeat unit can fold into single-handed helices giving rise to a non-linear enhancement of their chiroptical properties. Here, the authors ­report the stepwise growth of the first length-­defined enantiopure alleno-acetylenic oligomers. Starting with (P)-(+)-1, the hexadecameric homologue was assembled using an oxidative cross-coupling protocol (a) and a remarkably efficient monodeprotection (b) of the terminal acetonide groups. The analogous (M) isomer was also isolated and both enantiomers exhibited chiroptical properties that are among the most intense ever reported.