Universität zu Köln

Porada, Jan H., Neudoerfl, Joerg-M. and Blunk, Dirk ORCID: 0000-0001-6365-0404 (2015). Planar and distorted indigo as the core motif in novel chromophoric liquid crystals. New J. Chem., 39 (11). S. 8291 - 8302. CAMBRIDGE: ROYAL SOC CHEMISTRY. ISSN 1369-9261

Full text not available from this repository.

Abstract

Symmetrically bis-substituted indigo derivatives with long peripheral alkyl chains were synthesised by the reductive condensation of corresponding isatin derivatives. Their thermotropic mesomorphism was investigated with respect to different substitution patterns, which include the position and lateral modifications of the substituents. A systematic investigation of structure-property relationships revealed that only substitution at the 6 and 6' positions affords the calamitic shape necessary to form smectic or nematic liquid crystalline phases. This finding is rationalised on the basis of a structural analysis of N,N'-diacetyl indigo and the consequences for 5,5'- and 6,6'-bis-substituted derivatives are discussed. Some of the liquid crystalline substances exhibit dichroism, which is especially pronounced in highly ordered phases. In addition, the 6,6' substitution leads to significantly enhanced activity with respect to the photochemical trans-cis isomerization of N, N'-diacetylated indigo derivatives.

Item Type:	Journal Article
Creators:	Creators Email ORCID ORCID Put Code Porada, Jan H. UNSPECIFIED UNSPECIFIED UNSPECIFIED Neudoerfl, Joerg-M. UNSPECIFIED UNSPECIFIED UNSPECIFIED Blunk, Dirk UNSPECIFIED orcid.org/0000-0001-6365-0404 UNSPECIFIED
URN:	urn:nbn:de:hbz:38-415759
DOI:	10.1039/c5nj01594d
Journal or Publication Title:	New J. Chem.
Volume:	39
Number:	11
Page Range:	S. 8291 - 8302
Date:	2015
Publisher:	ROYAL SOC CHEMISTRY
Place of Publication:	CAMBRIDGE
ISSN:	1369-9261
Language:	English
Faculty:	Faculty of Mathematics and Natural Sciences
Divisions:	Faculty of Mathematics and Natural Sciences > Department of Chemistry > Institute of Organic Chemistry
Subjects:	no entry
Uncontrolled Keywords:	Keywords Language X-RAY; MOLECULES; REHYBRIDIZATION; DERIVATIVES; ANGEREGTEN; ALIGNMENT; ORDER; DYES Multiple languages Chemistry, Multidisciplinary Multiple languages
Refereed:	Yes
URI:	http://kups.ub.uni-koeln.de/id/eprint/41575