1253216-40-8Relevant articles and documents
Samarium(II) Iodide-Promoted Reactions of 2,3-Epoxycycloalkanone Hydrazones
Kang, Han-Young,Hong, Woo Sang,Lee, Sang Hak,Choi, Kyung Il,Koh, Hun Yeong
, p. 33 - 34 (1997)
The reaction of hydrazones of 2,3-epoxycycloalkanone promoted by samarium(II) iodide has been investigated to study the behavior of the compounds containing C=N bonds in the presence of this powerful single-electron transfer reagent. For the hydrazones derived from 2,3-epoxycyclopentanone and 2,3-epoxycyclohexanone, 3-iodo-2-cycloalkenols were isolated while the corresponding 2-cycloalkenols were the products when the hydrazones from 2,3-epoxycycloheptanone and 2,3-epoxycyclooctanone were reacted.
Cucurbit[5]uril-mediated electrochemical hydrogenation of α,β-unsaturated ketones
Sales, Ayrlane,de Oliveira e Castro, Isabela Andrade,de Menezes, Frederico Duarte,Selva, Thiago Matheus Guimar?es,Vilar, Márcio
, p. 295 - 305 (2019/09/03)
The potential of cucurbit[5]uril to be used as inverse phase transfer catalyst in electrocatalytic hydrogenation of α,β-unsaturated ketones is illustrated. The interaction behavior among isophorone and cucurbit[5]uril was also investigated using cyclic voltammetry and UV/vis absorption spectroscopy. The results concerning to both techniques revealed an enhancement in the intensity of the absorption peak and also in the current cathodic peak of isophorone in presence of cucurbit[5]uril. This achievement is related to the increase of the isophorone solubility in the medium being an indicative of a host-guest complex formation. The electrochemical hydrogenation of isophorone using cucurbit[5]uril was more efficient than others well-stablish methodologies. Regarding to (R)-(+)-pulegone and (S)-(+)-carvone, the use of cucurbit[5]uril leads to an increase of 17% and 9%, on average, respectively, in the yields when compared to the control reaction. The efficiency of selective C=O bond hydrogenation of 1-acetyl-1-cyclohexene was evaluated. The presence of cucurbit[5]uril increased by 12% the hydrogenations yields of 1-acetyl-1-cyclohexene when compared to the control reaction. In this sense, these results open up an opportunity to carry out electrocatalytic reactions within the cucurbit[5]uril environment.
Combining Photo-Organo Redox- and Enzyme Catalysis Facilitates Asymmetric C-H Bond Functionalization
Zhang, Wuyuan,Fueyo, Elena Fernandez,Hollmann, Frank,Martin, Laura Leemans,Pesic, Milja,Wardenga, Rainer,H?hne, Matthias,Schmidt, Sandy
supporting information, p. 80 - 84 (2019/01/04)
In this study, we combined photo-organo redox catalysis and biocatalysis to achieve asymmetric C–H bond functionalization of simple alkane starting materials. The photo-organo catalyst anthraquinone sulfate (SAS) was employed to oxyfunctionalise alkanes to aldehydes and ketones. We coupled this light-driven reaction with asymmetric enzymatic functionalisations to yield chiral hydroxynitriles, amines, acyloins and α-chiral ketones with up to 99 % ee. In addition, we demonstrate functional group interconversion to alcohols, esters and carboxylic acids. The transformations can be performed as concurrent tandem reactions. We identified the degradation of substrates and inhibition of the biocatalysts as limiting factors affecting compatibility, due to reactive oxygen species generated in the photocatalytic step. These incompatibilities were addressed by reaction engineering, such as applying a two-phase system or temporal and spatial separation of the catalysts. Using a selection of eleven starting alkanes, one photo-organo catalyst and 8 diverse biocatalysts, we synthesized 26 products and report for the model compounds benzoin and mandelonitrile > 97 % ee at gram scale.
