Abstract Formulations containing vinyl ethers and epoxy were successfully polymerized through a radical‐induced cationic frontal polymerization mechanism, using an iodonium salt superacid generator with a peroxide thermal radical initiator and fumed silica as a filler. It was found that an increase of vinyl ether content resulted in higher front velocities for divinyl ethers in formulations with trimethylolpropane triglycidyl ether. However, increased hydroxymonovinyl ether either decreased the front velocity or suppressed frontal polymerization. The kinetic effects of the superacid generator and thermal radical initiator with varying vinyl ether content were also studied. It was observed that increasing concentrations of initiators increased the front velocity, with the system exhibiting higher sensitivity to the superacid generator concentration.
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Rearrangement of a carboxy-substituted spiro[4.4]nonatriene to annulated fulvenes through a Pd( ii )-mediated 1,5-vinyl shift
A transformation of spiro[4.4]nonatrienes to aryl-substituted, enantioenriched annulated fulvenes is reported. DFT calculations and empirical results support a novel mechanism of reaction involving a 1,5-vinyl shift from a vinyl–palladium species.
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- Award ID(s):
- 2153972
- PAR ID:
- 10505424
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 14
- Issue:
- 42
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 11809 to 11817
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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