Templat-gesteuerte Synthese von Makrocyclen

Different macrocycles can be synthesized by using template directed synthesis. The template connects the building blocks of the macrocycle, so that the cyclization step between these building blocks can be performend easier. Well defined cyclic dimers can be synthesized using a bifunctional template. The ring closing step occurred by metathesis of the preorganized building blocks. The preorganization of the two building blocks simplifies the cyclisation step. After removal of the template the macrocycle can be obtained. Symmetric cyclophanes which possess internal amine groups can be synthesized by using symmetric templates as terephthaldialdehyd. The imine bonds are easy to prepare and to remove and therefore they are a good choice for introducing and removing of the template. Furthermore they don’t disturb the ring closing metathesis. If two different bulding blocks were used to prepare the cyclophane precursor an unsymmetrical cyclophane can be prepared. Another possibility to prepare the unsymmetrical diamine cyclophane is the template free preorganization of the building blocks. The prepared cyclophanes exhibit at least one functional group e.g. an amine group. These groups offer the opportunity to bind guests inside the macrocycles. Via protonation of these amines it should be possible to bind anions inside the macrocyle, too. Further on it was tried to prepare a molecular knot by using a metal ion as template. For this reason ligands were prepared which are composed of two different building blocks. The design of this ligand is of crucial importance. The subunits should be orthogonal to each other and one of the subunits has to contain to terminal double bonds and the other one has to possess a functionality which can bind to the metal ion. The linkage between the building blocks was performed via an imine or amide bond. The complexation of the ligand and titanium(IV) ions leads to the precursor of the molecular knot. Unfortunately the ring closing metathesis didn’t work in the desired way, so that the molecular knot couldn’t be prepared. An alternative which is based on triformylphloroglucinol was tried at the same time. In this case the precursor contains an organic template with three imine bridges which are additionally stabilized by three hydrogen bridges. However the ring closing metathesis hasn’t successfully performed yet.

Grantor dc:publisher

Mainz

Year dc:date

2007

Author dc:creator

• Yeni

Contributors dc:contributor

• Albrecht, Markus

• info:eu-repo/classification/ddc/540
• Cyclophane
• Template
• Makrocyclische Verbindungen
• Metathese <Chemie>
• Ringschlussmetathese
• Knoten <Chemie>
• Titankomplexe
• Chemie
• Chemische Synthese
• Template-Effekt
• cyclophanes
• templates
• makrocyclic compounds
• ring closing metathesis
• knots
• titanium complexes

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

ger

Identifier

https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-124107%22

OAI identifier oai:identifier

oai:publications.rwth-aachen.de:62543