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Updated: May 28, 2026

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
Synthesis of polyisoprene terpenoid dendrons and their applications in oligo(phenylene ethynylene)s as "shells"
Wen-Yu Chai1, Zi-Fa Shi, Peng An
1State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, PR China.
Abstract:
The novel double-stage convergent synthesis of a new class of polyisoprene terpenoid (PIPTP) dendrons is described. PIPTP dendrons bear a highly branched aliphatic hydrocarbon skeleton and a hydrophilic hydroxy focal point functionality. These dendrons have the specific formula C((5×2)(G+1)(-5))H((5×2)(G+2)(-8))O, and each dendritic layer is constructed from an isoprene unit. The key branching steps involve a double alkyl-metal addition to an ester functionality, followed by deoxygenation of the resulting tertiary alcohol by triethylsilane and trifluoroacetic acid, then hydrogenation or hydrogenolysis. The dendrons were also attached to oligo(phenylene ethynylene)s (OPEs) so as to function as protective shells to allow fine tuning of the nanoscopic environment around the OPE moiety, and to exert precise control of the packing density and intermolecular interaction between the OPE cores. Fluorescence quantum yield data reveal that the OPE core is better encapsulated by the PIPTP dendrons than by Fréchet dendrons.
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