7497-63-4Relevant academic research and scientific papers
A Library of Thermoresponsive, Coacervate-Forming Biodegradable Polyesters
Swanson, John P.,Monteleone, Leanna R.,Haso, Fadi,Costanzo, Philip J.,Liu, Tianbo,Joy, Abraham
, p. 3834 - 3842 (2015)
We report on a new class of thermoresponsive biodegradable polyesters (TR-PE) inspired by polyacrylamides and elastin-like proteins (ELPs). The polyesters display reversible phase transition with tunable cloud point temperatures (Tcp) in aqueous solution as evidenced by UV-vis spectroscopy, 1H NMR, and DLS measurements. These polyesters form coacervate droplets above their lower critical solution temperature (LCST). The Tcp of the polyesters is influenced by the solutes such as urea, SDS, and NaCl. The Tcp of the copolymers shows a linear correlation with the composition of the polyesters indicating the ability to tune the phase change temperature. We also show that such thermoresponsive coacervates are capable of encapsulating small molecules such as Nile Red. Furthermore, the polyesters are hydrolytically degradable.
Reduction of Activated Alkenes by PIII/PV Redox Cycling Catalysis
Longwitz, Lars,Werner, Thomas
supporting information, p. 2760 - 2763 (2020/02/05)
The carbon–carbon double bond of unsaturated carbonyl compounds was readily reduced by using a phosphetane oxide catalyst in the presence of a simple organosilane as the terminal reductant and water as the hydrogen source. Quantitative hydrogenation was observed when 1.0 mol % of a methyl-substituted phosphetane oxide was employed as the catalyst. The procedure is highly selective towards activated double bonds, tolerating a variety of functional groups that are usually prone to reduction. In total, 25 alkenes and two alkynes were hydrogenated to the corresponding alkanes in excellent yields of up to 99 %. Notably, less active poly(methylhydrosiloxane) could also be utilized as the terminal reductant. Mechanistic investigations revealed the phosphane as the catalyst resting state and a protonation/deprotonation sequence as the crucial step in the catalytic cycle.
REDUCTION METHOD USING WATER AS PROTON SOURCE BY MEANS OF N-HETEROCYCLIC CARBENE
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Paragraph 0014; 0015; 0018, (2016/10/10)
PROBLEM TO BE SOLVED: To provide a reduction method using water as a proton source by means of N-heterocyclic carbene, in which the N-heterocyclic carbene is used actively as a reaction accelerator to realize a hydrogenation reaction by using water as the proton source. SOLUTION: A solution, which is obtained by mixing: a reaction substrate shown at an upper stage of the following formulae; a precursor of the triazole-based N-heterocyclic carbene (NHC) shown at a lower stage; water; and 1,2-dimethoxyethane being a solvent, is reacted at 100°C or higher temperature for 2 hours or more while making the solution to pass through a microwave reaction unit and the reacted solution is subjected to reduced-pressure distillation to obtain a hydrogenated product. The formulae: (EWG1-EWG4 are each an ester group, a cyano group, a ketone group, an amido group or an imido group;R1-R5 are each a 1-20C aliphatic group, a 3-12C alicyclic group or 6-30C aromatic group) SELECTED DRAWING: None COPYRIGHT: (C)2016,JPO&INPIT
Transfer hydrogenation promoted by N-heterocyclic carbene and water
Kato, Terumasa,Matsuoka, Shin-Ichi,Suzuki, Masato
, p. 13906 - 13909 (2015/09/07)
N-Heterocyclic carbenes (NHCs) promote the transfer hydrogenation of various activated C=C, C=N, and N=N bonds with water as the proton source. The NHCs act as reducing reagents to be converted into their oxides. A detailed reaction mechanism is proposed on the basis of deuterium-labeling experiments.
A ONE-POT CONVERSION OF CYCLIC ANHYDRIDES TO ETHYL ω-DIALKYLAMINOALKANOATES
Bell, Kevin H.,Fullick, Graeme
, p. 1965 - 1970 (2007/10/02)
Ethyl ω-dialkylaminoalkanoates are conveniently obtained in good yield by a one-pot procedure from cyclic anhydrides by successive treatment with a secondary amine, triethyloxonium fluoroborate, and sodium borohydride.
