scholarly journals Rhodium-Catalyzed Reaction of Aryl- and Alkenylboronic Acids with 2,4-Dienoate Esters: Conjugate Addition and Heck Reaction Products.

ChemInform ◽  
2006 ◽  
Vol 37 (18) ◽  
Author(s):  
Gabriela de la Herran ◽  
Carmen Murcia ◽  
Aurelio G. Csaky
Keyword(s):  
Heck Reaction ◽  
Conjugate Addition ◽  
Reaction Products

Rhodium-Catalyzed Reaction of Aryl- and Alkenylboronic Acids with 2,4-Dienoate Esters:  Conjugate Addition and Heck Reaction Products†

2005 ◽  
Vol 7 (25) ◽  
pp. 5629-5632 ◽  
Author(s):  
Gabriela de la Herrán ◽  
Carmen Murcia ◽  
Aurelio G. Csákÿ
Keyword(s):  
Heck Reaction ◽  
Conjugate Addition ◽  
Reaction Products

scholarly journals Pd–NHC Catalyzed Conjugate Addition versus the Mizoroki–Heck Reaction

2011 ◽  
Vol 17 (11) ◽  
pp. 3091-3095 ◽  
Author(s):  
Aditya L. Gottumukkala ◽  
Johannes G. de Vries ◽  
Adriaan J. Minnaard
Keyword(s):  
Heck Reaction ◽  
Conjugate Addition

N1-Substituted Hypoxanthine Derivatives from the Reaction of 6-Halopurines with Michael Acceptors Under the Conditions of Heck Reaction

2000 ◽  
Vol 65 (5) ◽  
pp. 797-804 ◽  
Author(s):  
Martina Havelková ◽  
Martin Studenovský ◽  
Dalimil Dvořák
Keyword(s):  
Methyl Methacrylate ◽  
Butyl Acrylate ◽  
Heck Reaction ◽  
Conjugate Addition ◽  
Vinyl Ketone ◽  
Methyl Vinyl Ketone ◽  
Acetate Anion ◽  
Methyl Vinyl ◽  
Michael Acceptors

The reaction of 6-iodo-, 9-benzyl-6-chloropurine and 7-benzyl-6-chloropurine with butyl acrylate, acrylonitrile, methyl vinyl ketone or methyl methacrylate under conditions of the Heck reaction in the presence of TlOAc or AgOAc afforded N1-alkylhypoxanthine derivatives. Formation of these unexpected products can be rationalised as a Tl+- or Ag+-assisted substitution of halogen with acetate anion. The 6-acetoxypurine derivative thus formed then eliminates ketene and gives 7-benzyl- or 9-benzylhypoxanthine. Conjugate addition of these compounds onto Michael acceptors furnishes the N1-substituted hypoxanthine derivatives.

Efficient photocatalytic chemoselective and stereoselective C–C bond formation over AuPd@N-rich carbon nitride

2021 ◽  
Author(s):  
Heyan Jiang ◽  
Jie Xu ◽  
Sishi Zhang ◽  
Hongmei Cheng ◽  
Cuicui Zang ◽  
...  
Keyword(s):  
Visible Light ◽  
Heck Reaction ◽  
Carbon Nitride ◽  
Bond Formation ◽  
Reaction Products ◽  
Mild Conditions ◽  
Light Color

High unsymmetrical chemoselective Ullmann biaryl products and satisfactory Z-type stereoselective Heck reaction products could be achieved through changing the visible light color over AuPd@N-Rich carbon nitride under mild conditions.

ChemInform Abstract: Pd-NHC Catalyzed Conjugate Addition versus the Mizoroki-Heck Reaction.

ChemInform ◽  
2011 ◽  
Vol 42 (27) ◽  
pp. no-no
Author(s):  
Aditya L. Gottumukkala ◽  
Johannes G. de Vries ◽  
Adriaan J. Minnaard
Keyword(s):  
Heck Reaction ◽  
Conjugate Addition

Lead aspartate: a new en bloc stain for electron microscopy

1978 ◽  
Vol 36 (2) ◽  
pp. 34-35
Author(s):  
J.R. Walton
Keyword(s):  
Electron Microscopy ◽  
Calcium Ion ◽  
Enzyme Reaction ◽  
Lead Citrate ◽  
Reaction Products ◽  
En Bloc ◽  
Thin Sections ◽  
Lead Salts ◽  
Thin Sectioning ◽  
High Alkalinity

In electron microscopy, lead is the metal most widely used for enhancing specimen contrast. Lead citrate requires a pH of 12 to stain thin sections of epoxy-embedded material rapidly and intensively. However, this high alkalinity tends to leach out enzyme reaction products, making lead citrate unsuitable for many cytochemical studies. Substitution of the chelator aspartate for citrate allows staining to be carried out at pH 6 or 7 without apparent effect on cytochemical products. Moreover, due to the low, controlled level of free lead ions, contamination-free staining can be carried out en bloc, prior to dehydration and embedding. En bloc use of lead aspartate permits the grid-staining step to be bypassed, allowing samples to be examined immediately after thin-sectioning.Procedures. To prevent precipitation of lead salts, double- or glass-distilled H20 used in the stain and rinses should be boiled to drive off carbon dioxide and glassware should be carefully rinsed to remove any persisting traces of calcium ion.

Studies of Oxide Formation on Copper Thin Films by Electron Microscopy

1977 ◽  
Vol 35 ◽  
pp. 316-317
Author(s):  
G. G. Hembree ◽  
M. A. Otooni ◽  
J. M. Cowley
Keyword(s):  
Electron Microscopy ◽  
Electron Diffraction ◽  
Single Crystal ◽  
Crystal Surface ◽  
Crystal Defects ◽  
Diffraction Reflection ◽  
Reaction Products ◽  
Intermediate Energies ◽  
Crystal Films ◽  
Reflection Electron Microscopy

The formation of oxide structures on single crystal films of metals has been investigated using the REMEDIE system (for Reflection Electron Microscopy and Electron Diffraction at Intermediate Energies) (1). Using this instrument scanning images can be obtained with a 5 to 15keV incident electron beam by collecting either secondary or diffracted electrons from the crystal surface (2). It is particularly suited to studies of the present sort where the surface reactions are strongly related to surface morphology and crystal defects and the growth of reaction products is inhomogeneous and not adequately described in terms of a single parameter. Observation of the samples has also been made by reflection electron diffraction, reflection electron microscopy and replication techniques in a JEM-100B electron microscope.A thin single crystal film of copper, epitaxially grown on NaCl of (100) orientation, was repositioned on a large copper single crystal of (111) orientation.

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