Selective ring-opening metathesis polymerization (ROMP) of cyclobutenes. Unsymmetrical ladderphane containing polycyclobutene and polynorbornene strands

• Yuan-Zhen Ke,
• Shou-Ling Huang,
• Guoqiao Lai and
• Tien-Yau Luh

Beilstein J. Org. Chem. 2019, 15, 44–51, doi:10.3762/bjoc.15.4

• ][8][9][10][11][12][13][14][15] or from biscyclobutene [16] linked with a range of different rigid linkers. When a flexible linker is used, bisnorbornene derivatives undergo cascade metathetical cyclopolymerization giving the corresponding polynorbornenes with hammock-like pendants [17][18

• , therefore, the possibility for similar intramolecular metathesis cyclopolymerization might take place to form intermediate 16 for further transformations. However, no such reaction was observed in this study. Presumably, the 6-catalyzed metathesis reactivity of cyclobutenes would be much higher than that of

• . Cyclopolymerization of 15 with a flexible linker. Methanolysis of unsymmetrical ladderphane 8. Supporting Information Supporting Information File 10: 1H and 13C NMR spectra of both monomers and polymers, as well as GPC and kinetic investigation results. Acknowledgement We thank the Ministry of Science and

A tutorial review of stereoretentive olefin metathesis based on ruthenium dithiolate catalysts

• Daniel S. Müller,
• Olivier Baslé and
• Marc Mauduit

Beilstein J. Org. Chem. 2018, 14, 2999–3010, doi:10.3762/bjoc.14.279

• noted that very recently Grubbs and Choi employed Ru-3 for highly β-selective cyclopolymerization (not depicted in this review) [18]. Cross metathesis with cis-butendiol 12 was extensively explored by Hoveyda (Scheme 2c) [4]. The synthesis of Z-configured allylic alcohols is particularly attractive from

Highly reactive, liquid diacrylamides via synergistic combination of spatially arranged curing moieties

• Maximilian Maier,
• Magnus S. Schmidt,
• Markus Ringwald and
• Christoph P. Fik

Beilstein J. Org. Chem. 2017, 13, 372–383, doi:10.3762/bjoc.13.40

• synergistic combination of optimally arranged functional groups could be identified. The highest possible level of intramolecular synergism was found for low viscous N,N'-diacryloyl-N,N'-diallyl-1,4-but-2-enediamine. Keywords: acrylamide; allyl; cyclopolymerization; photopolymerization; spatial effect

• cyclopolymerization due to their adjacent double-bond functionalities [25][26][27]. The propagation reaction of these structures proceeds intramolecularly between acryl and allyl groups and intermolecularly (mostly) between polymer-radical and acrylamide groups. Cyclo- is preferred over linear polymerization due to

• 3). In order to verify an assumed, underlying cyclopolymerization mechanism, FTIR spectra of the crosslinkers were recorded before and after photopolymerization (Figure 6). All compounds containing both, acrylamido and allyl functions (1, 3–5), showed two peaks for the acrylamide vibration at ≈1645