556052-89-2Relevant academic research and scientific papers
Ordered structures and sub-5 nm line patterns from rod-coil hybrids containing oligo(dimethylsiloxane)
Fan, Xing-He,Luo, Longfei,Lyu, Xiaolin,Shen, Zhihao,Xiao, Anqi,Yang, Weilu,Zhang, Wei
, p. 10341 - 10344 (2020)
Sub-5 nm ordered nanostructures including lamellar, double gyroid, and columnar phases are formed by a series of oligo(dimethylsiloxane) (ODMS)-based rod-coil liquid crystals with accurate molecular weights. Films with well-oriented line patterns can be obtained by substrate-induced directed self-assembly, which may be further used as lithographic templates.
Template-directed synthesis of symmetric as well as unsymmetric macrocycles from rigid or flexible building blocks
Albrecht, Markus,Yeni
experimental part, p. 2451 - 2461 (2009/04/11)
'Arc'-shaped oligophenyl derivatives with terminal alkene moieties can be used to form macrocycles by 'dimerization' through ring-closing metathesis. Hereby the introduction of templates connecting the two building blocks favors the dimerization over oligomerization or polymerization reactions. Attachment of the template through imine formation allows the removal of the template simultaneous to the reduction of the double bonds formed during ring-closing metathesis. Unsymmetric macrocyles can be obtained either by successive attachment of different 'arc'-shaped molecules to the template or by direct imine connection of two different ring precursors. In the latter case, the imine unit cannot be cleaved in the case of the investigated examples but 'figure-8'-shaped macrobicycles are obtained. The studied template-directed macrocyclization depends on the one hand on the preorganization of the building blocks, and on the other on their flexibility. Georg Thieme Verlag Stuttgart.
Nontemplated versus templated synthesis of a 56-membered macrocycle
Albrecht, Markus,Yeni,Fr?hlich, Roland
, p. 2295 - 2297 (2008/02/09)
The amine-substituted quinquephenylene 1 was prepared in a Suzuki coupling approach and by reaction with terephthalic dialdehyde (7) it was transformed into the phenyl-connected diimine 8. Ring-closing metathesis with the Grubbs I or II catalyst led to the corresponding macrocycle 9. Hydrogenation resulted in the reduction of the double bonds as well as the removal of the template to yield the 56-membered macrocycle 6 in an overall yield of 43% (from 1). Direct metathesis reaction of 1 followed by hydrogenation afforded 6 in only 21% yield. Georg Thieme Verlag Stuttgart.
