Related Experiment Video
Updated: Dec 30, 2025

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Palladium Immobilized on Thiol-Modified Silica Gel for Effective Direct C-H Arylation
Shotaro Hayashi1, Atsushi Takigami1, Toshio Koizumi1
1Department of Applied Chemistry, National Defence Academy, 1-10-20 Hashirimizu, Yokosuka, 239-8686, Japan.
Abstract:
A palladium catalyst immobilized on thiol-modified silica gel (PITS) was developed for the efficient synthesis of various π-conjugated oligomers and polymers. Direct arylation of 3,4-ethylenedioxythiophene (EDOT) gave not only the corresponding oligomeric compounds in high yields but also high-molecular-weight π-conjugated polymers in high yields. Moreover, the polycondensation of the β-unprotected bithiophene monomer with dibromoarenes was also achieved. This solid-supported Pd catalyst was used to conduct regioselective direct arylation polycondensation, giving high-molecular-weight π-conjugated polymers in high purity (low levels of residual Pd impurities and structural β-defects).
Related Concept Videos
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Preparation of 1° Amines: Gabriel Synthesis
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
Preparation of Alkynes: Alkylation Reaction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
Preparation and Reactions of Sulfides
Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo,...

