81913-53-3

Upstream product

• 41252-83-9 2-bromo-2-phenylethanol 
• 2564-83-2 2,2,6,6-Tetramethyl-1-piperidinyloxy free radical 
• 65-85-0 benzoic acid 
• 161776-41-6 1-hydroxy-2-phenyl-2-(2',2',6',6'-tetramethyl-1'-piperidinyloxy)ethane 
• 100-42-5 styrene 
• 94-36-0 dibenzoyl peroxide 

Downstream Products

• 7031-93-8 2,2,6,6-tetramethylpiperidin-1-ol 
• 49594-84-5 Styrylbenzoat 
• 341968-36-3 1-(2-allyloxy-1-phenyl-ethoxy)-2,2,6,6-tetramethyl-piperidin 
• 161776-41-6 1-hydroxy-2-phenyl-2-(2',2',6',6'-tetramethyl-1'-piperidinyloxy)ethane 

Relevant academic research and scientific papers

The Photodynamic Covalent Bond: Sensitized Alkoxyamines as a Tool to Shift Reaction Networks Out-of-Equilibrium Using Light Energy

We implement sensitized alkoxyamines as "photodynamic covalent bonds" - bonds that, while being stable in the dark at ambient temperatures, upon photoexcitation efficiently dissociate and recombine to the bound state in a fast thermal reaction. This type of bond allows for the photochemically induced exchange of molecular building blocks and resulting constitutional variation within dynamic reaction networks. To this end, alkoxyamines are coupled to a xanthone unit as triplet sensitizer enabling their reversible photodissociation into two radical species. By studying the photochemical properties of three generations of sensitized alkoxyamines it became clear that the nature and efficiency of triplet energy transfer from the sensitizer to the alkoxyamine bond as well as the reversibility of photodissociation crucially depends on the structure of the nitroxide terminus. By employing the thus designed photodynamic covalent bonding motif, we demonstrate how to use light energy to shift a dynamic covalent reaction network away from its thermodynamic minimum into a photostationary state. The network could be repeatedly switched between its minimum and kinetically trapped out-of-equilibrium state by thermal scrambling and selective photoactivation of sensitized alkoxyamines, respectively.

CATALYTIC SYSTEMS FOR IMMORTAL RING-OPENING POLYMERISATION OF CYCLIC ESTERS AND CYCLIC CARBONATES.

The present invention discloses new catalyst systems based on complexes of divalent metals supported by chelating phenoxy ligands for immortal ring-opening polymerisation of cyciic esters and cyclic carbonates.

Multi-armed, TEMPO-functionalized unimolecular initiators for starburst dendrimer synthesis via stable free radical polymerisation. 2. Tris (1,3,5)benzyloxy unimers

The synthesis of the trifunctionalized TEMPO-modified unimolecular initiators, unimers I, II, and III is described. Unimer I was prepared via an SN2 type Williamson ether coupling of 1,3,5-tris(iodomethyl)benzene with a TEMPO-containing ethylbenzene hydroxy derivative. The synthesis of unimer II, however, was accomplished through SN1 reaction of 1,3,5-tris(bromomethyl)benzene with the hydroxy-ethylbenzene TEMPO derivative in the presence of silver triflate. Synthesis of unimer III started from phloroglucinol and an SNAr reaction with 1-fluoro-4-nitrobenzene, followed by reduction to the amino compound and Schiff base formation with the TEMPO-derivatized aromatic aldehyde. Stable free radical polymerisation (SFRP) of styrene and acetoxystyrene with unimer I are also described with molecular weights and polydispersities reported. It is concluded that the SFRP of styrene with a triradical initiator meets the requirements of a living system.

Bifunctional initiators for free radical polymerization of non-crosslinked block copolymers

Novel bifunctional initiators have been designed with functional groups that independently produce free radicals. Initiators were synthesized to contain both diazene (-N=N-) and 2,2,6,6-tetramethylpiperidinyl-1-oxy (TEMPO) moieties tethered by ester or ether linkages. It is anticipated that these compounds will be useful for producing a diverse number of block copolymers for applications in polymer-supported organic synthesis and materials science.