Designed pincer ligand supported Co(<scp>ii</scp>)-based catalysts for dehydrogenative activation of alcohols: Studies on <i>N</i>-alkylation of amines, α-alkylation of ketones and synthesis of quinolines
作者:Anshu Singh、Ankur Maji、Mayank Joshi、Angshuman R. Choudhury、Kaushik Ghosh
DOI:10.1039/d0dt03748f
日期:——
Base-metal catalysts Co1, Co2 and Co3 were synthesized from designed pincerligands L1, L2 and L3 having NNN donor atoms respectively. Co1, Co2 and Co3 were characterized by IR, UV–Vis. and ESI-MS spectroscopic studies. Single crystal X-ray diffraction studies were investigated to authenticate the molecular structures of Co1 and Co3. Catalysts Co1, Co2 and Co3 were utilized to study the dehydrogenative
Easy α-alkylation of ketones with alcohols through a hydrogen autotransfer process catalyzed by RuCl2(DMSO)4
作者:Ricardo Martínez、Diego J. Ramón、Miguel Yus
DOI:10.1016/j.tet.2006.07.013
日期:2006.9
indicate that the process goes through the oxidation of the alcohols with ruthenium (after a previous deprotonation) to yield the corresponding aldehyde and a ruthenium hydride intermediate. In turn, the aldehyde suffers a classical aldol reaction with the starting ketone to form the corresponding α,β-unsaturated ketone, which finally is reduced through a Michael-typeaddition by the aforementioned ruthenium
Efficient Organoruthenium Catalysts for α‐Alkylation of Ketones and Amide with Alcohols: Synthesis of Quinolines
<i>via</i>
Hydrogen Borrowing Strategy and their Mechanistic Studies
for C−C bond formation and exhibited excellent performance in the dehydrogenative coupling of ketones and amides. In the synthesis of C–C bonds, alcohols were utilized as the alkylating agent. A broad range of substrates, including sterically hindered ketones and alcohols, were well tolerated under the optimized conditions (TON up to 47000 and TOF up to 11750 h−1). This ruthenium (II) catalysts were
A novel and efficient method has been developed for the chemoselective conjugate reduction of α,β-unsaturatedketones with tosylhydrazine as a hydrogen source to the corresponding saturatedketones in moderate to good yields. The present protocol does not require the use of transitionmetal, and is efficient being applicable to a wide range of substrates (25 examples).
A transition metal-free α,β-dehydrogenation of ketones and aldehydes was developed. This reaction was conducted in a facile I2/KI/DMSO system to produce the corresponding unsaturatedcompounds in good to high yields. The gram-scale experiment also indicated the potential synthetic value of this new reaction in organic synthesis. In the reaction, DMSO acted as both solvent and mild oxidant.
研究了酮和醛的无过渡金属α,β-脱氢反应。该反应在容易的I 2 / KI / DMSO系统中进行,以高至高收率生产相应的不饱和化合物。克级实验还表明了这种新反应在有机合成中的潜在合成价值。在反应中,DMSO既充当溶剂又充当弱氧化剂。