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Although the palladium-catalyzed Suzuki-Miyaura cross-coupling of aryl esters has received significant attention, there is a lack of methods that utilize cheap and readily accessible Pd-phosphane catalysts, and can be routinely carried out with high cross-coupling selectivity. Herein, we report the first general method for the cross-coupling of pentafluorophenyl esters (pentafluorophenyl = pfp) by selective C–O acyl cleavage. The reaction proceeds efficiently using Pd(0)/phosphane catalyst systems. The unique characteristics of pentafluorophenyl esters are reflected in the fully selective cross-coupling vs. phenolic esters. Of broad synthetic interest, this report establishes pentafluorophenyl esters as new, highly reactive, bench-stable, economical, ester-based, electrophilic acylative reagents via acyl-metal intermediates. Mechanistic studies strongly support a unified reactivity scale of acyl electrophiles by C(O)–X (X = N, O) activation. The reactivity of pfp esters can be correlated with barriers to isomerization around the C(acyl)–O bond.
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Exploring high molecular weight vinyl ester polymers made by PET-RAFT
Polyvinyl esters are used in many applications, however, high molecular weight polyvinyl esters have many challenges, with strategies for the synthesis of these polymers being the focus of this work.
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- PAR ID:
- 10504564
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Polymer Chemistry
- Volume:
- 15
- Issue:
- 9
- ISSN:
- 1759-9954
- Page Range / eLocation ID:
- 868 to 877
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D4PY00065J
