925-78-0Relevant articles and documents
METHOD FOR CONVERTING HYDROXYL GROUP OF ALCOHOL
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Paragraph 0493-0494, (2021/02/19)
The present invention relates to: a method for converting a hydroxyl group of an alcohol; and a catalyst which makes the method possible. A method for converting a hydroxyl group of an alcohol according to the present invention is characterized by producing a compound represented by CH(R1)(R2)Nu (wherein R1, R2 and Nu are as defined below) by reacting an alcohol represented by CH(R1)(R2)OH (wherein each of R1 and R2 represents a hydrogen atom, an optionally substituted alkyl group, or the like) and a compound having an active proton, which is represented by H-Nu (wherein Nu represents a group represented by —CHX1-EWG1 or —NR3R4; X1 represents a hydrogen atom or the like; EWG1 represents an electron-withdrawing group; and each of R3 and R4 represents a hydrogen atom, an optionally substituted alkyl group, or the like), with each other in the presence of a complex of a group 7-11 metal of the periodic table and at least one solid base that is selected from the group consisting of layered double hydroxides, composite oxides and calcium hydroxide.
C -Methylation of Alcohols, Ketones, and Indoles with Methanol Using Heterogeneous Platinum Catalysts
Siddiki, S. M. A. Hakim,Touchy, Abeda S.,Jamil, Md. A. R.,Toyao, Takashi,Shimizu, Ken-Ichi
, p. 3091 - 3103 (2018/04/14)
A versatile, selective, and recyclable heterogeneous catalytic method for the methylation of C-H bonds in alcohols, ketones, and indoles with methanol under oxidant-free conditions using a Pt-loaded carbon (Pt/C) catalyst in the presence of NaOH is reported. This catalytic system is effective for various methylation reactions: (1) the β-methylation of primary alcohols, including aryl, aliphatic, and heterocyclic alcohols, (2) the α-methylation of ketones, and (3) the selective C3-methylation of indoles. The reactions are driven by a borrowing-hydrogen mechanism. The reaction begins with the dehydrogenation of the alcohol(s) to afford aldehydes, which subsequently undergo a condensation reaction with the nucleophile (aldehyde, ketone, or indole), followed by hydrogenation of the condensation product by Pt-H species to yield the desired product. In all of the methylation reactions explored in this study, the Pt/C catalyst exhibits a significantly higher turnover number than other previously reported homogeneous catalytic systems. Moreover, it is demonstrated that the high catalytic activity of Pt can be rationalized in terms of the adsorption energy of hydrogen on the metal surface, as revealed by density functional theory calculations on different metal surfaces.
Regioselective Isomerization of 2,3-Disubstituted Epoxides to Ketones: An Alternative to the Wacker Oxidation of Internal Alkenes
Lamb, Jessica R.,Mulzer, Michael,Lapointe, Anne M.,Coates, Geoffrey W.
supporting information, p. 15049 - 15054 (2015/12/08)
We report an alternative pathway to the Wacker oxidation of internal olefins involving epoxidation of trans-alkenes followed by a mild and highly regioselective isomerization to give the major ketone isomers in 66-98% yield. Preliminary kinetics and isotope labeling studies suggest epoxide ring opening as the turnover limiting step in our proposed mechanism. A similar catalytic system was applied to the kinetic resolution of select trans-epoxides to give synthetically useful selectivity factors of 17-23 for benzyl-substituted substrates.
