Zobrazeno 1 - 10
of 12
pro vyhledávání: '"Arnon Olankitwanit"'
Publikováno v:
J Am Chem Soc
We report an air-stable diradical dication of chiral D(2)-symmetric conjoined bis[5]diazahelicene with unprecedented high spin (triplet) ground state, singlet triplet energy gap, ΔE(ST) = 0.3 kcal mol(−1). The diradical dication possesses closed-s
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::39906e6b1ffb4ac2054f62bfc1a07104
https://doi.org/10.1021/jacs.9b08711
https://doi.org/10.1021/jacs.9b08711
Publikováno v:
Journal of the American Chemical Society. 139:7144-7147
We report a large kinetic isotope effect at 298 K, kH/kD ≈ 150, associated with an intramolecular 1,5-hydrogen atom transfer (1,5-HAT) in the decay of a PEGylated carbazyl (aminyl) radical in solution. The experimental observations surprisingly com
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a91675fda73a615245135b172c9e29d0
https://doi.org/10.1021/jacs.7b02692
https://doi.org/10.1021/jacs.7b02692
Publikováno v:
The Journal of Organic Chemistry. 80:5035-5044
Aminyl diradical 3, a derivative of aza-m-xylylene, is expected to be more stable than diradical 1, due to increased steric protection of the radicals by additional methyl groups in the pendant group. Here we report synthesis and characterization of
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::1e2363db6e86c392e84643086d80bbb9
https://doi.org/10.1021/acs.joc.5b00421
https://doi.org/10.1021/acs.joc.5b00421
Publikováno v:
Journal of the American Chemical Society. 136:14277-14288
We describe synthesis and characterization of a derivative of aza-m-xylylene, diradical 2, that is persistent in solution at room temperature with the half-life measured in minutes (∼80-250 s) and in which the triplet ground state is below the lowe
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a8e90d8a40897881f1c3059ccb217ad5
https://doi.org/10.1021/ja508119d
https://doi.org/10.1021/ja508119d
Publikováno v:
Journal of the American Chemical Society. 138(23)
We report a relatively persistent, open-shell aza-thia[7]helicene with cross-conjugated electron-rich π-system. The singly occupied molecular orbital (SOMO) energy levels of both radical cation and neutral radical of the [7]helicene are below the hi
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cc35ba64e1972df573da09cc5bfe37bd
https://pubmed.ncbi.nlm.nih.gov/27219299
https://pubmed.ncbi.nlm.nih.gov/27219299
Publikováno v:
Journal of the American Chemical Society. 133:4750-4753
Organic molecules with a strong preference for triplet ground states, in which the triplet state is below the lowest singlet state by ≥10 kcal/mol, are typically short-lived and mostly detected as reactive intermediates. We now report a triplet gro
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d84fbe29542ddfd277820f0ec6a9b794
https://doi.org/10.1021/ja200708b
https://doi.org/10.1021/ja200708b
Publikováno v:
The Journal of organic chemistry. 80(3)
Organic molecules with high-spin ground states, besides being fundamentally interesting, possess numerous potential applications in diverse fields such organic magnetism, MRI contrast agents, and spintronics. Such molecules, once thought to exist onl
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0ec72283d2f1fc18794cc27d3f9573ff
https://pubmed.ncbi.nlm.nih.gov/25574756
https://pubmed.ncbi.nlm.nih.gov/25574756
Autor:
Ying Wang, Maren Pink, Suchada Rajca, Andrzej Rajca, Przemysław J. Boratyński, Arnon Olankitwanit
Publikováno v:
Journal of the American Chemical Society. 135(48)
Aminyl tetraradicals with planar tetraazanonacene backbones have quintet (S = 2) ground states and do not show any detectable thermal population of the low-spin excited states up to the highest temperature investigated (100 K) in the 2-methyltetrahyd
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0bcd626ae16414c41f4a5f64ab5e3a5b
https://pubmed.ncbi.nlm.nih.gov/24251582
https://pubmed.ncbi.nlm.nih.gov/24251582
Autor:
Sandra S. Eaton, Deborah G. Mitchell, Gareth R. Eaton, Andrzej Rajca, Michael A. Swanson, Ying Wang, Arnon Olankitwanit, Suchada Rajca, Michael D. Boska, Joseph T. Paletta
We report a molecular design that provides an intravenously injectable organic radical contrast agent (ORCA) for which the molecular 1H water relaxivity (r1) is ca. 5 mM–1 s–1. The ORCA is based on spirocyclohexyl nitroxide radicals and poly(ethy
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0f586ad1b158dae40d634247618d1f78
https://europepmc.org/articles/PMC3486519/
https://europepmc.org/articles/PMC3486519/
Publikováno v:
Organic letters. 14(12)
Asymmetric synthesis of (-)-[9]helicene, as well as preparation of its lower homologues, completes the series of carbon-sulfur [5]-, [7]-, [9]-, and [11]helicenes. Spectroscopic and electrochemical studies of this series provide an absorption onset-b
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::95923545112a09dfc7feab6f1e137058
https://pubmed.ncbi.nlm.nih.gov/22651843
https://pubmed.ncbi.nlm.nih.gov/22651843