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1.
Cell ; 187(4): 810-812, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38364786

RESUMO

Jaye Antoinette Wilson is a winner of the fourth annual Rising Black Scientists Award for a scholar in the physical, data, earth, and environmental sciences. We asked emerging Black scientists to tell us about their scientific vision and goals, experiences that sparked their interest in science, how they want to contribute to a more inclusive scientific community, and how these all fit together on their journey. This is her story.


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Distinções e Prêmios , Ciência Ambiental , Animais , Pesquisadores , Borboletas
2.
JACS Au ; 2(2): 515-521, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35253000

RESUMO

Rigorous investigations of the organobase-catalyzed ring-opening polymerizations (ROPs) of a series of five-membered cyclic carbonate monomers derived from glucose revealed that competing transcarbonylation reactions scrambled the regiochemistries of the polycarbonate backbones. Regioirregular poly(2,3-α-d-glucose carbonate) backbone connectivities were afforded by 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD)-catalyzed ROPs of three monomers having different cyclic acetal protecting groups through the 4- and 6-positions. Small molecule studies conducted upon isolated unimers and dimers indicated a preference for Cx-O2 vs Cx-O3 bond cleavage from tetrahedral intermediates along the pathways of addition-elimination mechanisms when the reactions were performed at room temperature. Furthermore, treatment of isolated 3-unimer or 2-unimer, having the carbonate linkage in the 3- or 2-position as obtained from either Cx-O2 or Cx-O3 bond cleavage, respectively, gave the same 74:26 (3-unimer:2-unimer) ratio, confirming the occurrence of transcarbonylation reactions with a preference for 3-unimer vs. 2-unimer formation in the presence of organobase catalyst at room temperature. In contrast, unimer preparation at -78 °C favored Cx-O3 bond cleavage to afford a majority of 2-unimer, presumably due to a lack of transcarbonylation side reactions. Computational studies supported the experimental findings, enhancing fundamental understanding of the regiochemistry resulting from the ring-opening and subsequent transcarbonylation reactions during ROP of glucose carbonates. These findings are expected to guide the development of advanced carbohydrate-derived polymer materials by an initial monomer design via side chain acetal protecting groups, with the ability to evolve the properties further through later-stage structural metamorphosis.

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