Poly(oxanorbornenedicarboximide)s dendronized with amphiphilic poly(alkyl ether) dendrons

Abstract

Attaching dendritically branched side chains to each repeat unit of a linear polymer produces molecular building blocks of nanometer‐sized dimensions called dendronized polymers. The structure of these complex molecular architectures is highly tunable and, therefore, of interest for a wide range of potential applications. The first examples of dendronized polymers prepared by living ring‐opening metathesis polymerization of oxanorbornenedicarboximide macromonomers with poly(alkyl ether) dendrons are reported. Small‐angle X‐ray scattering experiments on bulk samples confirm that the diameter of the individual cylindrical polymers can be tailored by the choice of dendron generation or the length of the hydrocarbon peripheral group. Analysis of the SAXS data based on a core‐shell model indicates that although the diameter of the cylinder increases with generation, the size of the core does not change; this suggests that these dendrons only loosely encapsulate the polymer backbone. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 3221–3239

Synthesis and Self-Assembly of Bundle-Forming α-Helical Peptide–Dendron Hybrids

“…Dietherification of methallyl dichloride with 6 under Williamson conditions afforded the second-generation alkene 7 . We have previously noted that 15-crown-5 improves the efficiency of the generational growth step in the synthesis of poly(alkyl ether) dendrons, 34 and this modification was employed in the synthesis of 7 . Dendritic alcohol 8 was obtained from hydroboration-oxidation of 7 .…”

“…We also investigated syntheses of 13 and 14 (Scheme 5). Chemoselective debenzylation of 12 34a under oxidative conditions 35 yielded 13 but the product was difficult to isolate from the reaction mixture. An attempt to synthesize 14 in a fully convergent manner similar to that described by Cho and co-workers 36 was abandoned because tedious chromatographic purifications were needed to obtain dendrons of acceptable purity.…”

The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2014

“…77) [363], fluorescent groups and PEG groups (copolymer) [364]; polyoxometallates [365], dendriditically connected to a polylactate and a polystyrene system [366], and dendritic connection to anthraquinone moieties [367]; (19) bis(norbornenesuccinimide)s connected through a perylene ring [368]; (20) aza-Diels-Alder derived azanorbornenes (e.g. 80) [369]; (21) oxanorbornenes connected to azide groups [370]; (22) oxanorbornenecuccinic anhydride (81) [371]; (23) oxanorbornenesuccinimides, including those connected to alkyne groups [372], and to dendrimeric systems [373,374]; and (24) oxanorbornenedicarboxylate esters connected to guanidine groups [375]. The kinetic resolution of a racemic oxanorbornene (e.g.…”

ROMP of supramolecular norbornene monomers containing β-cyclodextrin–ferrocene (/adamantane) inclusion complexes

“…Cp), 4.15 (broad, free Cp), 3.69-3.55 (m, CONCH 2 , H-6, H-3, and H-5 of β-CD), 3.41-3.28 (m, CH 2 NHCO, H 2 O, H-2 and H-4 of β-CD), 3.01 (broad, =CH-CH), 2.69 (broad, CONCH), 1.90 (broad, CH 2 of cyclopentane), 1.42 (broad, CH 2 of cyclopentane). 13 C NMR (100 MHz, (CD 3 ) 2 SO, 25°C, TMS), δ ppm : 178.1 (CON), 162.3 (CONH), 137.1, and 136.5 (CH=CH), 101.9 (C-1 of β-CD), 81.5 (C-4 of β-CD), 73.1 (C-3 of β-CD), 72.4 (C-5 of β-CD), 72.1 (C-2 of β-CD), 69.9, 69. 4 A similar procedure was adopted to synthesize P (NAd@β-CD) as a white powder.…”

“…Thus, using this technique, various well-defined homopolymers and copolymers, whose polydispersity indexes (PDIs) are normally less than 1.2, can be prepared for all kinds of functional applications, such as their use in drug delivery [7], bioimaging [8], and catalysis [9], along with their preparation as nanoparticles [10] and hydrogels [11]. Through the use of norbornene-based monomers, polynorbornenes with various types of configurations can be synthesized, such as brush polymers [12], dendronized polymers [13], branched polymers [14], star polymers [15], ladderphanes [16], and multicyclic polymers [17][18][19]. The extensive application of ROMP is attributed to the high group tolerance of Grubbs' catalyst [1,20].…”