75091-92-8Relevant articles and documents
Accessing Difluoromethylated and Trifluoromethylated cis-Cycloalkanes and Saturated Heterocycles: Preferential Hydrogen Addition to the Substitution Sites for Dearomatization
Zhang, Xue,Ling, Liang,Luo, Meiming,Zeng, Xiaoming
supporting information, p. 16785 - 16789 (2019/11/11)
Reported here is a straightforward process in which a cyclic (alkyl)(amino)carbene/Rh catalyst system facilitates the preferential addition of hydrogen to the substitution sites of difluoromethylated and trifluoromethylated arenes and heteroarenes, leading to dearomative reduction. This strategy enables the diastereoselective synthesis of cis-difluoromethylated and cis-trifluoromethylated cycloalkanes and saturated heterocycles, and even allows formation of all-cis multi-trifluoromethylated cyclic products with a defined equatorial orientation of the di- and trifluoromethyl groups. Deuterium-labeling studies indicate that hydrogen preferentially attacks the substitution sites of planar arenes, resulting in dearomatization, possibly with heterogeneous Rh as the reactive species, followed by either reversible or irreversible hydrogen addition to the nonsubstitution sites.
Hydrogen-free ring hydrogenation of phenol to cyclohexanol over a rhodium-loaded titanium(IV) oxide photocatalyst
Kinoshita, Atsufumi,Nakanishi, Kousuke,Yagi, Ryosuke,Tanaka, Atsuhiro,Hashimoto, Keiji,Kominami, Hiroshi
, p. 83 - 88 (2019/04/13)
Since photocatalytic reactions are almost consistent with the concept of green chemistry, substance conversion using photocatalysts has recently attracted the attention of researchers in the fields of organic chemistry, physical chemistry and material chemistry. We investigated photoinduced ring hydrogenation of phenol over a metal-loaded titanium(IV) oxide (TiO2) photocatalyst without the use of H2 gas and we report here the effects of various parameters, including the type and amount of metal co-catalyst loaded on TiO2 and the kinds of solvents and hole scavengers, on the ring hydrogenation. We found that the combination of an Rh co-catalyst, water and oxalic acid resulted in the highest yield of cyclohexanol. Detailed analyses revealed that phenol was first hydrogenated to cyclohexanone via keto-enol tautomerism of cyclohexenol followed by hydrogenation of cyclohexanone to cyclohexanol and that adsorption of phenol onto Rh-TiO2 is a factor of great importance for the ring hydrogenation.
MELANOCORTIN RECEPTOR AGONISTS
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Page/Page column 27, (2008/06/13)
The present invention relates to a compound of the following formula 1, pharmaceutically acceptable salt and isomer thereof effective as agonist of melanocortin receptor, and an agonistic composition of melanocortin receptor comprising the same as active ingredient.