A unique
Through thiol‐ene photopolymerization of presynthesized oligomers, advanced clickable nucleic acids (CNA‐2G) are synthesized with sequence‐controlled repeating units. As examples, poly(thymine‐adenine) (polyTA) CNA‐2G and poly(thymine‐thymine‐cytosine) CNA‐2G are synthesized by polymerizing thiol‐ene heterofunctional dimers with pendant thymine‐adenine nucleobases and trimer with pendant thymine‐thymine‐cytosine nucleobases. Based on size exclusion chromatography (SEC) analysis, polyTA and polyTTC have number average molecular weights of 2000 and 1800, respectively, which contain 7–8 pendant nucleobases. Based on the different behavior of the CNA‐2G monomers and CNA‐2G oligomers with two or more pendant nucleobases in photopolymerization, an unusual thiol‐ene chain‐growth propagation mechanism is observed for the former and a common thiol‐ene step‐growth propagation mechanism for the latter. The uncommon thiol‐ene chain‐growth propagation is hypothesized to rely on a six‐membered ring mediated intramolecular hydrogen atom transfer process.
more » « less- NSF-PAR ID:
- 10456804
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Rapid Communications
- Volume:
- 41
- Issue:
- 16
- ISSN:
- 1022-1336
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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