Experimental observations show that direct olefin epoxidation by H(2)O(2), which is extremely sluggish otherwise, occurs in fluorinated alcohol (R(f)OH) solutions under mild conditions requiring no additional catalysts. Theoretical calculations of ethene and propene epoxidation by H(2)O(2) in the gas phase and in the presence of methanol and of two fluorinated alcohols, presented in this paper, show that the fluoro alcohol itself acts as a catalyst for the reaction by providing a template that stabilizes specifically the transition state (TS) of the reaction. Thus, much like an enzyme, the fluoro alcohol provides a complementary charge template that leads to the reduction of the barrier by 5-8 kcal mol(-)(1). Additionally, the fluoro alcohol template keeps the departing OH and hydroxyalkenyl moieties in close proximity and, by polarizing them, facilitates the hydrogen migration from the latter to form water and the epoxide product. The reduced activation energy and structural confinement of the TS over the fluoro alcohol template render the epoxidation reaction observable under mild synthetic conditions.
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http://dx.doi.org/10.1021/jo034087t | DOI Listing |
Hematol Oncol
November 2024
Department of Clinical Medicine and Surgery, Federico II University Medical School, Naples, Italy.
In elderly patients with high-risk classic Hodgkin lymphoma (c-HL), we evaluated the impact of a new modality treatment without bleomycin, that is, liposomal doxorubicin (NPLD)-based regimen plus consolidation radiotherapy of residual nodal masses (RNMs), on overall survival (OS) and progression free survival (PFS). In this retrospective study (2013-2023) conducted in tertiary hospitals in the bay of Naples (Italy), 50 older adults (median age, 69 years; range, 60-89) with advanced stage c-HL received frontline treatment with MVD ± irradiation. MVD consisted of 25 mg/m of NPLD along with standard Vinblastine and Dacarbazine for a total of 6 cycles (twelve iv administrations, every 2 weeks) followed by radiation of RNMs with size ≥ 2.
View Article and Find Full Text PDFDalton Trans
December 2024
School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiangxi, China.
Org Lett
November 2024
Urumqi Key Laboratory of Green Catalysis and Synthesis Technology, Key Laboratory of Oil and Gas Fine Chemicals, Ministry of Education & Xinjiang Uygur Autonomous Region, State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi 830017, P. R. China.
Nucl Med Biol
December 2024
Department of Gynecology, Leiden University Medical Center, Leiden, the Netherlands. Electronic address:
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