2111-75-3Relevant articles and documents
New sustainable synthetic routes to cyclic oxyterpenes using the ecocatalyst toolbox
Bihanic, Camille,Grison, Claude,Lasbleiz, Arthur,Le Blainvaux, Pierre,Petit, Eddy,Regnier, Morgan
, (2021/12/09)
Cyclic oxyterpenes are natural products that are mostly used as fragrances, flavours and drugs by the cosmetic, food and pharmaceutical industries. However, only a few cyclic oxyterpenes are accessible via chemical syntheses, which are far from being ecofriendly. We report here the synthesis of six cyclic oxyterpenes derived from ?-pinene while respecting the principles of green and sustainable chemistry. Only natural or biosourced catalysts were used in mild conditions that were optimised for each synthesis. A new generation of ecocatalysts, derived from Mn-rich water lettuce, was prepared via green processes, characterised by MP-AES, XRPD and TEM analyses, and tested in catalysis. The epoxidation of ?-pinene led to the platform molecule, ?-pinene oxide, with a good yield, illustrating the efficacy of the new generation of ecocatalysts. The opening ?-pinene oxide was investigated in green conditions and led to new and regioselective syntheses of myrtenol, 7-hydroxy-α-terpineol and perillyl alcohol. Successive oxidations of perillyl alcohol could be performed using no hazardous oxidant and were controlled using the new generation of ecocatalysts generating perillaldehyde and cuminaldehyde.
Efficient aerobic oxidation of alcohols catalyzed by NiGa hydrotalcites in the absence of any additives
Sun, Fuan,Zhou, Jiacheng,Zhou, Weiyou,Pan, Jiugao,Qian, Junfeng,He, Mingyang,Chen, Qun
, p. 4029 - 4035 (2018/03/21)
The aerobic oxidation of alcohol catalyzed by NiGa hydrotalcites in the absence of any additives has been studied in detail. The research results revealed that the surface basicity significantly affected the catalytic performance. Moreover, the Br?nsted OH basic site on Ni-containing hydrotalcites was suggested to be the key active site and accelerated the oxidation. The catalytic system had good tolerance for various alcohols, and an excellent selectivity of aldehyde could be obtained for the oxidation of primary alcohol. A probable non-radical reaction path for the transformation has been proposed according to the catalytic results, isotope labelling experiments and Hammett experiments.
Selective Oxidation of Activated Alcohols by Supported Gold Nanoparticles under an Atmospheric Pressure of O2: Batch and Continuous-Flow Studies
Giorgi, Pascal D.,Elizarov, Nelli,Antoniotti, Sylvain
, p. 1830 - 1836 (2017/05/29)
In the hunt for a simple, mild, and scalable protocol for gold nanoparticle-catalyzed oxidation of benzylic and allylic alcohols under O2, we have used commercially available gold nanoparticles supported on alumina to selectively oxidize a large range of activated alcohols to the corresponding carbonyl compounds in good yields (68–99 %) and with excellent selectivity (ca. 100 %). The true heterogeneous nature of the catalysis by gold was demonstrated, allowing us to further adapt this protocol to continuous-flow reactors by using the tube-in-tube technology, in which higher yields were obtained thanks to an improved oxygenation of the reaction medium.