15356-60-2Relevant articles and documents
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Read,Grubb
, p. 188,193 (1931)
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Stereoselective reduction of menthone by molecularly imprinted polymers
Hedin-Dahlstroem, Jimmy,Shoravi, Siamak,Wikman, Susanne,Nicholls, Ian A.
, p. 2431 - 2436 (2004)
Polymeric chiral reductants selective for the reduction of (-)-menthone 1 to the diastereomeric products (-)-menthol 2 and (+)-neomenthol 3 were prepared by a covalentmolecular imprinting using 2 as the template. The LiAlH4 derivatized imprinted polymers altered the natural outcome of the reduction reaction (LiAlH4) from 2:1 [(-)-menthol:(+)-neomenthol] to 1:1. The reaction mechanism is discussed in terms of reaction site structure. The molecularly imprinted polymers demonstrated enantioselective recognition for 2 (0.15μmol enantioselective sites/g polymer) in batch binding experiments.
Apple-tree shoots and transformed carrot and apple roots used as biocatalysts in enantioselective acetate hydrolysis, alcohol oxidation and ketone reduction
Mironowicz, Agnieszka,Kromer, Krystyna
, p. 1655 - 1662 (1998)
(±)-1-Phenylethyl (1), (±)-1-(1-naphthyl)ethyl (2), (±)-1-(2-naphthyl)ethyl (3) and (±)-menthyl (4) acetates were hydrolyzed using apple-tree shoots and hairy roots of carrot and apple-tree to afford alcohols, which, subsequntly, in the same environment, were oxygenated to ketones. Pure (S)-1-(2-naphthyl)ethanol ((S)-(-)-7), (R)-1-phenylethyl acetate ((R)-(+)-1), (R)-1-(1-naphthyl)ethyl acetate ((R)-(+)-2). (S)-1-phenylethanol ((S)-(-)-5) and (-)-menthol (1R,25,5R)-(-)-8) have been produced.
Continuous synthesis of menthol from citronellal and citral over Ni-beta-zeolite-sepiolite composite catalyst
Er?nen, Kari,M?ki-Arvela, P?ivi,Martinez-Klimov, Mark,Muller, Joseph,Murzin, Dmitry Yu.,Peurla, Markus,Simakova, Irina,Vajglova, Zuzana
, (2022/04/03)
One-pot continuous synthesis of menthols both from citronellal and citral was investigated over 5 wt% Ni supported on H-Beta-38-sepiolite composite catalyst at 60–70 °C under 10–29 bar hydrogen pressure. A relatively high menthols yield of 53% and 49% and stereoselectivity to menthol of 71–76% and 72–74% were obtained from citronellal and citral respectively at the contact time 4.2 min, 70 °C and 20 bar. Citral conversion noticeably decreased with time-on-stream under 10 and 15 bar of hydrogen pressure accompanied by accumulation of citronellal, the primary hydrogenation product of citral, practically not affecting selectivity to menthol. A substantial amount of defuctionalization products observed during citral conversion, especially at the beginning of the reaction (ca. 1 h), indicated that all intermediates could contribute to formation of menthanes. Ni/H-Beta-38-sepiolite composite material prepared by extrusion was characterized by TEM, SEM, XPS, XRD, ICP-OES, N2 physisorption and FTIR techniques to perceive the interrelation between the physico-chemical and catalytic properties.
Light-Induced Formation/Scission of C-N, C-O, and C-S Bonds Enables Switchable Stability/Degradability in Covalent Systems
Hai, Yu,Li, Ziyi,Lu, Hanwei,Ye, Hebo,You, Lei,Zou, Hanxun
supporting information, p. 20368 - 20376 (2021/12/03)
The manipulation of covalent bonds could be directed toward degradable, recyclable, and sustainable materials. However, there is an intrinsic conflict between properties of stability and degradability. Here we report light-controlled formation/scission of three types of covalent bonds (C-N, C-O, and C-S) through photoswitching between equilibrium and nonequilibrium states of dynamic covalent systems, achieving dual benefits of photoaddressable stability and cleavability. The photocyclization of dithienylethene fused aldehyde ring-chain tautomers turns on the reactivity, incorporating/releasing amines, alcohols, and thiols reversibly with high efficiency, respectively. Upon photocycloreversion the system is shifted to kinetically locked out-of-equilibrium form, enabling remarkable robustness of covalent assemblies. Reaction coupling allows remote and directional control of a diverse range of equilibria and further broadens the scope. Through locking and unlocking covalent linkages with light when needed, the utility is demonstrated with capture/release of bioactive molecules, modification of surfaces, and creation of polymers exhibiting tailored stability and degradability/recyclability. The versatile toolbox for photoswitchable dynamic covalent reactions to toggle matters on and off should be appealing to many endeavors.