ENANTIOPURE TRIOXADECALIN DERIVED LIQUID CRYSTALS: INFLUENCE OF PHENYL SUBSTITUTION ON THE MESOGENIC PROPERTIES

Abstract

Nickel(0)-catalyzed reaction of pseudo-glucal 1 with Grignard reagents derived from bromobenzene and 1-bromo-4-phenylbenzene gives the corresponding β-C-aryl glycosides 2. Desilylation and hydrogenation of 2 leads to saturated β-C-aryl glycosides 4, which can be used as chiral intermediates in the synthesis of chiral liquid crystals. The combination with p-alkoxy-substituted benzaldehyde leads to compounds 5–6. Alternatively, reaction with p-alkoxy-substituted phenylboronic acids gives the bora analogues 7–9. The mesogenic properties of these compounds are strongly influenced by the presence of an additional phenyl ring in the molecule.

ACKNOWLEDGMENTS

C. M. and B. B. thank the French Ministery of Education for a fellowship. Financial support by DAAD/Procope Programme is gratefully acknowledged.