Palladium-Catalyzed Heterofunctionalization of C-H, C=C and C≡ C Bonds

Abstract

The heterofunctionalisation of C-H, C=C and C C bonds is an important type of transformation that converts readily accessible precursors to valuable intermediates in organic synthesis, particularly when the heteroatom = N or O. The progress in this area of homogeneous catalysis by palladium is described in the current review, covering the period between 2005-early 2010. Asymmetric reactions remain a key challenge in this area, which is highlighted.

Chemicals from Alkynes with Palladium Catalysts

“…The palladium-catalyzed addition of amines to alkynes (hydroamination) leads to an enamine, which, according to the nature of the amine, can remain or evolve as an imine (or can be hydrolyzed to a ketone). This methodology has experienced a considerable research and success in the case of the intramolecular version, as many nitrogen-containing heterocyclic systems, as indoles, can be obtained in this way (see section 3.2), its intermolecular counterpart being however much less explored. ,, Recent uses of palladium complexes for the intermolecular preparation of these nitrogenated systems can be seen in Scheme in the synthesis of acetophenone imines, such as 98 , by reaction of aromatic amines, such as 2,6-dimethylaniline, with phenylacetylene. This reaction is catalyzed by the CSC-pincer palladium complex 96 (1 mol %) in the presence of triflic acid (5 mol %) as additive in toluene as solvent at 100 °C .…”

Recent Advancement in Palladium-Catalyzed C–C Bond Activation of Strained Ring Systems: Three- and Four-Membered Carbocycles as Prominent C3/C4 Building Blocks

“…Palladium as a catalyst has been extensively used by the scientific community to synthesize various drugs, natural products, and bioactive scaffolds . Its practical utility as a catalyst has been exploited in various C–X bond activation strategies.…”