Beyond the Tebbe Olefination: Direct Transformation of Esters into Ketones or Alkenes
作者:Anna M. Domżalska-Pieczykolan、Bartłomiej Furman
DOI:10.1055/s-0039-1691594
日期:2020.4
A direct, effective, and operationally simple transformation of esters into ketones or alkenes by the exclusive action of Tebbe’s reagent has been developed. The transformation utilizes the dual character of Tebbe’s reagent as both a methylenation agent and a rearrangement catalyst in the reaction of a wide range of substituted vinyl ethers. The resulting transformation involves sequential methylenation
DDQ-Catalyzed Oxidative CO Coupling Of sp<sup>3</sup>CH Bonds With Carboxylic Acids
作者:Hong Yi、Qiang Liu、Jie Liu、Ziqi Zeng、Yuhong Yang、Aiwen Lei
DOI:10.1002/cssc.201200458
日期:2012.11
catalytic amounts of DDQ combined with MnO2 as oxidant, an efficient oxidative CO coupling of benzylic sp3 CH bonds with carboxylic acids affords a series of carboxylic esters in 70–98 % yields. A wide range of functional groups and various carboxylic acids are tolerated. The reaction involves both CH functionalization and CO bond formation.
possess a core-shell nanostructure with the diameter of around 110 nm. The resulting polymeric nanoreactors showed excellent catalytic activity for acylation of alcohols in water. High conversion of a variety of alcohol (>99%) and excellent product selectivity were achieved. The high catalytic efficiency of the nanoreactors may be attributed to the enhancement of the interaction between the reactant and
reagent was polymerized through reversible addition-fragmentation chain transfer (RAFT) polymerization in situ in water, leading to simultaneous amphiphilic block copolymer formation and self-assembly. The diameters of the resulted micelles ranged from 20 to 100 nm depending on the type and amount of hydrophilic monomer, and solid content is up to 25%. The high catalytic activity of the micelles as homogeneous
Provided are a writing instrument produced at a lower cost than conventional thermochromic writing instruments utilizing frictional heat, slim like a pencil and not bulky because it contains an ink directly in a barrel thereof, and excellent in portability; and a set of the writing instruments.
The writing instrument 1 is obtained by directly filling a barrel thereof with an ink 2 which becomes colorless or colored, or undergoes a color change by heating and an ink follower 5 following the ink with its consumption; firmly fixing a writing tip portion 3 to the end of the barrel directly or via a relay member; and disposing a friction body 6 having an elasticity at the rear end portion of the barrel. The writing instrument set has a plurality of the writing instruments respectively different from each other in color tone.