Benzylic triflates prepared in-situ: novel initiators for mono-, bi- and trifunctional living poly(THF)s

Abstract

Marina Lathouri provides a critical overview of the historiography of typology, tracing the word ‘type’ back to its 18th‐century origins and through to its re‐emergence as a standardised objet‐type in the Modernist era. She closes by questioning the pertinence of type and typology today.

Synthesis of Polymeric Topological Isomers through Electrostatic Self‐Assembly and Covalent Fixation with Star Telechelic Precursors

“…A solution (1.0 mL) of a trifunctional star-shaped poly(THF) precursor carrying triflate counteranions [24] (0.400 g, 0.039 mmol) in tetrahydrofuran (THF) was added dropwise to an ice-cooled (<5 8C) aqueous solution (120 mL) containing an excess amount of a sodium terephthalate (0.123 g, 10 equiv.) under vigorous stirring.…”

“…[12,22,23] It is notable that such multicyclic, polymeric topological isomers are common products in the equimolar reaction of not only linear but also branched polymer precursors with polyfunctional end-linking reagents. [12] Moreover, the selective synthesis of y-shaped polymers has been achieved by a trifunctional star-shaped poly(THF) precursor (1S) [24] Summary: A pair of macromolecular constitutional isomers having topologically distinctive, dicyclic constructions, that is, y-shaped and manacle-shaped polymers, has been synthesized from a polymer self-assembly, comprised of threearmed star poly(tetrahydrofuran) [poly(THF)] having N-phenylpyrrolidinium salt end groups carrying dicarboxylate counteranions (1S/2d). The presence of the two constitutional polymeric isomers was confirmed by means of a reversed-phase liquid chromatography (RPC) technique.…”

Condensation reactions of guanidines with bis-electrophiles: formation of highly nitrogenous heterocycles

“…However, the methylation step was problematic due to the propensity of methyl triflate to polymerize THF. 22 The optimal solvent for this two-step reaction sequence was found to be chlorobenzene (PhCl), which was both inert to the reaction conditions and could safely be heated to 95-100 °C under sealed tube conditions (Table 1, Entry 3). The aminolysis step was found to proceed smoothly on multigram scale (2.5 g) with ammonium acetate or ammonium chloride as additives in the presence of ammonia.…”

Synthesis and Characterization of Hydroxy-telechelic Four-arm Star-shaped Oligo(tetrahydrofuran), Their Crosslinking, and Thermomechanical Investigation of the Poymer Network

“…In general, linear and star-shaped PTHF can be obtained by ringopening polymerization of tetrahydrofuran (THF) by living cationic polymerization, which enables a good control of the reaction and the polymer structure. Different living functional initiator systems were reported for the synthesis of PTHF of various architectures and reactive end groups [19][20][21][22][23][24]. A four-armed star-shaped PTHF could be synthesized from photoinduced cationic polymerization of THF and pentaerythritol tetrakis (3,4-epoxybutanoate) in the presence of diphenyliodonium hexafluorophosphate [19].…”