Iron-Catalyzed, Hydrogen-Mediated Reductive Cyclization of 1,6-Enynes and Diynes: Evidence for Bis(imino)pyridine Ligand Participation
作者:Kevin T. Sylvester、Paul J. Chirik
DOI:10.1021/ja902478p
日期:2009.7.1
The bis(imino)pyridine iron dinitrogen complex (((i)Pr)PDI)Fe(N(2))(2) catalyzes the hydrogen-mediated reductivecyclization of enynes and diynes with turnover frequencies comparable to those of established precious metal catalysts. Amino, oxygenated, and carbon-based substrates are readily cyclized to the corresponding hetero- and carbocycles with 5 mol % iron and 4 atm H(2) at 23 degrees C. Stoichiometric
Ruthenium-Catalyzed Conjugate Hydrogenation of α,β-Enones by in situ Generated Dihydrogen from Paraformaldehyde and Water
作者:Wanfang Li、Xiao-Feng Wu
DOI:10.1002/ejoc.201403359
日期:2015.1
Notwithstanding that the highly selective hydrogenation of α,β-enones to allylic alcohols can be realized by using Noyori's Ru bifunctional system, the selective reduction of the C=C bonds in α,β-enones without touching the C=O bonds still lacks a general, simple, and efficient procedure. Ruthenium-catalyzed conjugate hydrogenation of various α,β-enones to saturatedketones with high selectivity was investigated
The Liquid-phase Oxidation of Methylbenzenes by the Cobalt-Copper-Bromide System
作者:Toshihiko Okada、Yoshio Kamiya
DOI:10.1246/bcsj.54.2724
日期:1981.9
The liquid-phase oxidation of methylbenzenes catalyzed by a catalyst system composed of cobalt(II) and copper(II) acetates and sodium bromide was carried out in acetic acid at 150 °C. The corresponding benzyl acetates and benzaldehydes were obtained in high selectivities in most cases. A nuclear-brominated product, i.e., 3-bromo-4-methoxytoluene was also obtained in the oxidation of p-methoxytoluene
由乙酸钴(II)和乙酸铜(II)和溴化钠组成的催化剂体系催化甲基苯的液相氧化,在乙酸中于 150 °C 下进行。在大多数情况下,以高选择性获得相应的乙酸苄酯和苯甲醛。在对甲氧基甲苯的氧化中也得到核溴化产物,即3-溴-4-甲氧基甲苯,其具有两个不同的反应位点,即供电子甲氧基取代基的邻位和苄基位。然而,在催化剂体系中溴离子取代乙酸根离子对侧链氧化产物具有令人满意的选择性。在对二甲苯氧化中,还得到了α,α'-二乙酰氧基-对二甲苯和对(乙酰氧基甲基)苯甲酸,以及对甲基乙酸苄酯,虽然他们的金额很小。还进行了多甲基苯的氧化。
XY–ZH Systems as potential 1,3-dipoles. Part 8. Pyrrolidines and Δ<sup>5</sup>-pyrrolines (3,7-diazabicyclo[3.3.0]octenes) from the reaction of imines of α-amino acids and their esters with cyclic dipolarophiles. Mechanism of racemisation of α-amino acids and their esters in the presence of aldehydes
Imines of α-aminoacidesters with aromatic, heterocyclic, and aliphatic aldehydes generate azomethine ylides stereospecifically by a prototropic shift on heating in toluene. The azomethine ylides undergo cycloaddition to N-phenylmaleimide, maleic anhydride, and p-naphthoquinone via an endo-transition state to give racemic, single diastereoisomeric, cycloadducts. α-Aminoacids undergo analogous cycloadditions
Rational Design of Acyldiphenylphosphine Oxides as Photoinitiators of Radical Polymerization
作者:Céline Dietlin、Thanh Tam Trinh、Stéphane Schweizer、Bernadette Graff、Fabrice Morlet-Savary、Pierre-Antoine Noirot、Jacques Lalevée
DOI:10.1021/acs.macromol.9b01724
日期:2019.10.22
efficient acylphosphine oxides have been used for many years as photoinitiators of radicalpolymerization. As very few new acylphosphine oxide compounds have been proposed these past years for the radicalpolymerization of methacrylates, the aim of this work is to use molecular modeling to select potentially reactive compounds before their synthesis to see whether acyldiphenylphosphine oxide (ADPO) molecules